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Class - IX 3 Eduheal Foundation

CLASS ‐ IX S. No. Category Topic Page No.

1. Syllabus Guide Line 04

2. Experiment Put Spin on it 06

3. Explore Why it Happen 07

4. Discover Careful! Do not Mix...... 10

5. Discover Balloon Inflating Without Blowing 11

6. Experiment Quick or Slow 13

7. Explore and Activity Chloroplast and Mitochondria 15

8. Explore Journey from Atoms to Polymers 18

9. Invent Your Own Telescope 22

10. Experiment Centre of Gravity 24

11. Discover The Amazing Water Tricks 26

12. Activity Wider World 29

13. Experiment Hot and Cold Chemistry 31

14. Discover Floating Soap Bubble 34

15. Invent Salt Volcano 36

16. Invent Seccret Chime 38

17. Invent Can Bongo 40

18. Experiment Layered Liquid 43

19. Explore Adaptation 44

20. Experiment Glittering Liquids 45

21. Experiment Find the Bacteria Hiding in Your Milk 49

22. Interactivity Activity Mission Microbe 51

4 Class - IX Eduheal Foundation

CLASS VIII Matter in our surroundings – Characteristics and states of matter, Change of State and Evaporation The fundamental unit of Life – Structure of a Cell, cell organelles Motion – Uniform and Non-Uniform motion, distance-displacement, velocity and acceleration Is matter around us pure – Mixtures, types of mixtures, solution, colloids, Suspension Methods of separation of mixtures, compounds, Element, Physical And Chemical Change Tissues – Types of plant tissues and animal tissues Force and Laws of Motion – Force, definition and its effects, Three laws of motion, Mass, Inertia and Conservation of Momentum Atoms and Molecules – Laws of Chemical combination, Definition of atoms and molecules, Chemical Formulae. Diversity In Living Organisms – Classification of Plants Classification of animals and nomenclature. Gravitation – Universal law of gravitation, free - fall, mass and weight. Thrust and pressure, Archimedes principle, relative density.

*


Structure of Atom – Atomic number, Mass number, Valency, Isotopes and Isobars Electronic Distribution – Rutherford‛s Model and Bohr Model. Diseases and its causes Infectious and Non-infectious diseases, Principles of treatment and prevention Work and Energy – Work done by a force, power and energy Kinetic energy and potential energy, laws of conservation of energy Natural Resources – Air, water and soil, pollution of air and water. Nitrogen Cycle, Carbon cycle, Water cycle, Oxygen Cycle, Green House Effect, Ozone Layer. Sound – Propagation of sound – longitudinal and transverse waves. Characteristics of sound waves, structure of human ear (qualitative), Multiple reflection of sound. Application of Ultrasound Improvement in food resources, Improvement in crop yield Manure and fertilizers, cropping patterns, animal husbandry, poultry and fish farming, bee-keeping.

* Kindly note that Syllabus guidelines are given for present class but 90% question paper of NISO will be based on previous class syllabus.


Eggs have a number of uses in our day-to-day life. Your birthday cake or the pastries you often eat has eggs. They form an important ingredient in many recipes. But besides this, can you imagine that an egg, too can help you in explaining laws of science. Come! lets know how .....

You Will Need Hard-boiled egg

Uncooked egg

Here’s How: 1 Spin the hard-boiled egg on a smooth surface. Stop the egg, then let it go right away.

2 Spin the uncooked egg on a smooth surface. Stop the egg, then let it go right away.

3 Watch what happens when you let go of the eggs.

What’s Happening The uncooked egg should spin a little even after you stop it. Newton‛s first law explains why: when an object is moving, it tends to continue moving at the same speed unless acted upon by an outside force. When you stop the uncooked egg, you stop the shell—the yolk and white are not attached to the shell so they keep moving.

After you have tried this a few times, you can amaze your family and friends—ask them to mix up the eggs, and then use what you‛ve learned to figure out which egg is uncooked!

Put Spin On it


Q. Why Do Onions Make You Cry?

You might have avoided cooking, but probably you have cut up an onion and experienced the burning and tearing you get from the vapours.

When you cut an onion, you break cells, releasing their contents. Amino acid sulphoxides form sulphenic acids. Enzymes that were kept separate, now are free to mix with the sulphenic acids to produce propanethiol sulphur oxide, a volatile sulphur compound that wafts upward toward your eyes. This gas reacts with the water in your tears to form sulphuric acid. The sulphuric acid burns, stimulating your eyes to release more tears to wash the irritant away.

Cooking the onion inactivates the enzyme, so while the smell of cooked onions may be strong, it doesn‛t burn your eyes. Aside from wearing safety goggles or running a fan, you can keep from crying by refrigerating your onion before cutting it (it slows reactions which can change the chemistry inside the onion) or by cutting the onion under water.

The sulphur-containing compounds also leave a characteristic odour on your fingers when you cut an onion.

Q. Why Does Ice Float?

There are two parts to the answer for this question. First, let‛s take a look at why anything floats. Then, let‛s examine why ice floats on top of liquid water, instead of sinking to the bottom.

Why It Happens?


A substance floats if it is less dense, or has less mass per unit volume, than other components in a mixture. For example, if you toss a handful of rocks into a bucket of water, the rocks, which are dense compared to the water, will sink. The water, which is less dense than the rocks, will float. Basically, the rocks push the water out of the way, or displace it. For an object to be able to float, it has to displace a weight of fluid equal to its own weight.

Water reaches its maximum density at 4°C. As it cools further and freezes into ice, it actually becomes less dense. On the other hand, most substances are most dense in their solid (frozen) state than in their liquid state. Water is different because of hydrogen bonding.

A water molecule is made from one oxygen atom and two hydrogen atoms, strongly joined to each other with covalent bonds.

Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a litre of ice weighs less than a litre of water. The heavier water displaces the lighter ice, so ice floats to the top. One consequence of this is that lakes and rivers freeze from top to bottom, allowing fish to survive even when the surface of a lake has frozen over. If ice sank, the water would be displaced to the top and exposed to the colder temperature, forcing rivers and lakes to fill with ice and freeze solid.

O

H H


Q. Can a Candle Burn in Zero Gravity?

Yes, a candle can burn in zero gravity. However, the flame is quite different. Fire behaves differently in space and microgravity than on Earth.

A microgravity flame forms a sphere surrounding the wick. Diffusion feeds the flame with oxygen and allows carbon dioxide to move away from the point of combustion, so the rate of burning is slowed. The flame of a candle burned in microgravity is an almost invisible blue colour.

Smoke and soot production is different for candles and other forms of fire in space or zero gravity compared to candles on earth. Unless air flow is available, the slower gas exchange from diffusion can produce a soot-free flame.

However, when burning stops at the tip of the flame, soot production begins. Soot and smoke production depends on the fuel flow rate.

lWhen scientists broke open molecules, they found they were only stuffed with atoms. But when they broke open atoms, they found them stuffed with explosions l Teacher: What is the formula for water? Student: H, I, J, K, L, M, N, O Teacher: That‛s not what I taught you. Student: But you said the formula for water is...H to O !!


Some of the common chemicals found in your home shouldn‛t be mixed together. It‛s one thing to say “don‛t mix bleach with ammonia”, but it‛s not always easy to know what products contain these two chemicals. Here‛s are some products you may have around the home that shouldn‛t be combined.

Bleach with Acid Toilet Bowl Cleaners

This mixture can result in toxic, potentially deadly fumes.

Bleach with Vinegar

Vinegar is a type of acid. Toxic chlorine vapour is produced. Don‛t mix chlorine bleach with any acid.

Bleach with Ammonia

Toxic, potentially lethal vapours are produced.

Different Brands of One Type of Product

Don‛t mix different cleaners together. They may react violently, produce toxins, or become ineffective.

Highly Alkaline Products with Highly Acidic Products

Acids and bases (alkalies) can react violently, presenting a splash hazard.

Acids and bases are caustic and may cause chemical burns.

Careful! Do Not Ever Mix!!


Balloon Inflating Without Blowing! You often have to blow hard to inflate a balloon on birthdays or any other occassion. But in this experiment you will perform & see how a balloon inflates on its own.

You will need One small party balloon

One small bottle.

A kettle

What to do? Boil the kettle. Ask the adult to put 1 tablespoon of water from the kettle into the empty bottle. The bottle will be very hot and full of steam at this point. Ask the adult to hold the bottle still on a table.

After 20 seconds stretch the opening of the party balloon over the mouth of the bottle. Now stand back and let the bottle cool off with the balloon covering the opening.

Notice that as the bottle cools, the balloon gets sucked into the bottle. If you had just the right amount of water left when you put the balloon on the bottle, the balloon will actually ‘inflate‛ into the bottle until it fills the whole inside!

What is happening? When water boils it becomes steam. As the water boils away,

the steam fills the whole inside of the bottle. If you had just

Note :– Ask an adult to supervise you


taken the bottle and set it on the table to cool without adding the balloon, the steam would have cooled and condensed back into a very small amount of water. The water is smaller than the steam and takes up less space so more air is needed to fill the gap. This comes through the open bottle neck.

What you did in this experiment was put a rubber balloon in the way of the air trying to get back in the bottle and the balloon is pulled inside instead. If you were really lucky it would have inflated inside the bottle!

Down 1. a positively charged

particle found in the nucleus of an atom

3. a very small piece or part; an indivisible object

5. the central part of an atom

7. something that has mass which can exist in the form of a soild, liquid, gas or plasma

Across 2. a neutral particle made of three quarks found in the nucleus of an atom 4. a tiny particle with a negative charge which orbits an atom's nucleus 6. the smallest unit of a chemical element 9. two or more elements that are chemically joined 10. an instrument that uses lenses to produce magnified images of very small objects

Cross Word Puzzle

Search for answers!


Reaction time, in humans, is the elapsed time between the receiving of stimuli & the subsequent reaction. So, how quick do you think you are? With the help of a friend, you can find out.

Here’s How: Ask your friend to hold a wooden ruler (30 inch ruler) from the top so that it is up and down with the bottom several feet above the floor. Your friend may have to stand on a chair to do this.

You hold your fingers opposite the 18-inch mark, but don‛t touch the stick! Without warning, your friend should let go of the yard stick, and you should try to catch it with your fingers.

Notice what inch mark your fingers are on when you catch the stick. Subtract this number from 18 or subtract 18 from the number to see how many inches the stick fell before you caught it. Try it several times to see if you get the same answer. Let your friend try to catch it while you drop it. Who has the quickest reaction time? Your reaction time can be determined from the table given below:

Distance dropped Reaction time 2 inches 0.10 seconds 4 inches 0.14 seconds 6 inches 0.18 seconds 8 inches 0.20 seconds 10 inches 0.23 seconds 12 inches 0.25 seconds 14 inches 0.27 seconds 16 inches 0.29 seconds 18 inches 0.31 seconds

Quick or Slow ?


Why? Why do you think it takes time for your fingers to react when your eyes see the stick start to fall? Can you think of reasons the reaction time might be different for an adult and a child? Perhaps you could test your theory with several adults and children.

Fun Science Facts l The blue whale can produce sounds up to 188 decibels. This is the

loudest sound produced by a living animal and has been detected as far away as 530 miles.

l The human eye blinks an average of 4,200,000 times a year. l The longest living cells in the body are brain cells which can live an

entire lifetime. l The hottest planet in the solar system is Venus, with an estimated

surface temperature of 864 F (462ºC). l Hydrofluoric acid will dissolve glass. l No matter its size or thickness, no piece of paper can be folded in half

more than 7 times. l Diamonds are the hardest substance known to man. l The highest temperature on Earth was 136 F (58°C) in Libya in 1922. l Chimps are the only animals that can recognize themselves in a mirror. l The common goldfish is the only animal that can see both infra-red and

ultra-violet light. l Rats multiply so quickly that in 18 months, two rats could have over 1

million descendents. l An Astronaut can be up to 2 inches taller returning from space. The

cartilage disks in the spine expand in the absence of gravity.


Plant cells contain an organelle called the chloroplast. The chloroplast allows plants to harvest energy from sunlight. Specialized pigments in the chloroplast (including the common green pigment chlorophyll) absorb sunlight and use this energy to complete the chemical reaction:

6 CO + 6 H O 2 2 Sunlight (Energy)

C H O + 6O 12 6 2 6

In this way, plant cells manufacture glucose and other carbohydrates that they can store for later use. Photosynthetic cells may have thousands of chloroplasts. Chloroplasts are double membrane organelles with an inner membrane folded into disc- shaped sacs called thylakoids. Colour and label the outer membrane light green. Thylakoids, containing chlorophyll and other accessory pigments, are in stacks called granum (grana, plural). Colour and label the grana dark green in Figure 1. Grana are connected to each other by structures called lamellae, and they are surrounded by a gel-like material called stroma. Colour and label the lamellae brown in figure 1. Colour and label the stroma light blue in Figure 1. Light-capturing pigments in the grana are organized into photosystems. In Figure 2, colour and label a single thylakoid (stack) dark green. In another stack in figure 2, colour and label a granum red.

Mitochondria are the powerhouses of the cell. Glucose and other carbohydrates made by plants during photosynthesis are broken down by the process of aerobic cellular respiration in the mitochondria of the cell. This releases energy (ATP) for the cell.

Chloroplasts and Mitochondria


The more active a cell (such as a muscle cell), the more mitochondria it will have. The mitochondria are about the size of a bacterial cell and are often peanut-shaped. Mitochondria have a double membrane like the nucleus and chloroplast. The outer membrane is smooth, while the inner membrane is convoluted into folds called cristae. Colour and label the outer membrane pink and the cristae red in figure 3. This greatly increases the surface area of the membrane so that carbohydrates (simple sugars) can combine with oxygen to produce ATP, adenosine triphosphate (the energy molecule of the cell). The electron transport chain takes place across the membranes of the cristae (crista, singular). Inside the folds or cristae is a space called the matrix that contains enzymes needed for the Kreb‛s Cycle. Colour and label the matrix yellow in figure 3.

Figure 1-Chloroplast

Figure 2-Thylakoid


Fig. 3-Mitochondria

Now try to find out the answer of following Questions: 1. What is the energy molecule of the cell called?

2. What macromolecule made by plants is “burned” in the mitochondria?

3. Where is chlorophyll found in the chloroplast?

4. In which part of a plant would you expect to find the most chloroplasts and why?

5. How would the number of mitochondria in an insect‛s wing compare to the amount found in other cells in an insect‛s body? Explain your answer.


Protons, Neutrons, and Electrons! Protons and neutrons together spin at the center of the atom, deep within, while all around, electrons wildly race But most of the atom is empty space!! Energy holds it all together (millions of atoms at the tip of a feather!)

The electron is minus, the proton is plus, the neutron is neither, without a fuss.

Elements are the kinds of atoms we have; most are natural, some are made in the lab. If you know the number of protons, you‛re able to find the element on the periodic table.

When two atoms join and share their electrons, they hold hands to form a covalent bond. Groups of atoms together are molecules. In polymers, they‛re strung together like jewels!

My rhymes I fear are beginning to strain, So in the rest of this page these will be explained!

At the very center of each atom is the nucleus. The nucleus is a cluster of particles called protons and neutrons. Protons have a plus (+) charge, and neutrons are neutral (that is, they don‛t have a charge).

The nucleus is very compact, and even though it accounts for most of an atom‛s weight, it takes up a very small amount of the atom‛s total volume.

Journey from Atoms to Polymers


As a matter of fact, most of the atom is empty space! The rest of the atom has electrons whizzing around it like crazy. Electrons have a minus (-) charge, and so there are enough electrons to balance out the (+) protons. Electrons are so light, though, that they really don‛t count towards the total weight of the atom.

But electrons don‛t fly around just anywhere. They have set amounts of energy. The more energy an electron has, the further away from the nucleus it tends to be. The outermost electrons are called the valence electrons. Valence electrons have a special job - they can form bonds - or connect - with another atom.

Atoms can have as many as 8 valence electrons. (Hydrogen and helium, those little troublemakers, can have 2, but no more.) A carbon atom has 4 valence electrons.

Name two elements which have 6 valence electron and 2 valence electron.

The kinds of atoms that exist are called elements. Some elements are: silver, gold, neon, and carbon. To see all of the elements in one place, look at a periodic table given in your book. All of the elements that exist are there on the periodic table, starting with hydrogen at number 1, on up to more than 100. That number, called the atomic number tells how many protons each atom has. So, hydrogen has 1 proton, carbon has 6 protons, and nickel has 28 protons. Every element has a symbol of one or two letters. Some of them make sense, like carbon is C and oxygen is O, and some of them don‛t, like the symbol for gold, Au. (Actually, Au is based on the Latin word for gold, aurum.)

Can you name three more element whose symbol don‛t have much sense.


When atoms join together, they form bonds.

A Bonding Experience There are two basic kinds of bonds - covalent and ionic.

Covalent bonds happen when two atoms share electrons - kind of like 2 atoms holding hands. When at least 2 atoms get together by sharing electrons, they form a molecule.

Ionic bonds happen when one atom gives at least one electron to another atom. Isn‛t that nice?!

Two atoms sit next to each other. One atom needs an electron, and the other atom has an extra electron. Perfect! Once the electron gets handed over, the atoms are no longer atoms - they‛re ions, and they each have a charge - one plus (+ positive) and one minus (- negative).

Remember that each atom started with enough (-) electrons to match each (+) proton in its nucleus. The atom that gets an extra electron ends up with a (-) charge and is called an anion. The atom that gives away an electron ends up with a (+) charge and is called a cation.

A comes before C

N comes before P

Anions are Negative

Cations are Positive


Now, those (+) and (-) charges have a strong attraction to each other - they sit next to each other and refuse to move. And guess what? That‛s an ionic bond! - the strong attraction between ions with opposite charges. Table salt is a good example of a common ionic compound. (Table salt is also called sodium chloride.)

What about polymers? How are they bonded together? Polymer backbones are held together by covalent bonds - by atoms sharing electrons. Other atoms, or even groups of atoms, hook onto the backbone by covalent bonds too.

Some polymers that are called ionic polymers have ionic pendant groups. Their backbones are still held together by covalent bonds. When it comes to polymers, all of their backbones are held together by covalent bonds (that is, by sharing electrons).

Polymer are commonly used in our day to day life.

Name a type of Polymer cloth.


Have you ever seen a telescope. If not, then go to the nearest Science Planetarium or Science Museum. Look at the amazing night sky through it. But in this activity you are going to make your own telescope at home ...

You will Need: A pair of “Weak” glasses—those with

low numbers (It will work the best)

A magnifying glass A flashlight

Masking tape A piece of waxed paper

A friend

To Do and Observe You‛re about to make a telescope. One lens of the reading glasses will serve as the objective lens of the telescope—the lens that gathers light from stars or other objects. The magnifying glass will be the eyepiece. This telescope won‛t have a tube—that‛s so you can see how an image is formed inside a

telescope.

Here’s How 1 To keep your “objective lens” steady, tape the glasses to a coat rack, the back of a chair, or any other object, making sure that one lens sticks out into space.

Your Own Telescope


2 Set the flashlight on a table four meters (thirteen feet) or more from the glasses. Turn the flashlight on and shine it at the lens.

3 Hold the paper in front of the lens on the side opposite from the flashlight. Then walk away from the lens, perhaps as far as a meter, until you see a small image of the flashlight on the paper. Normally, this image is formed inside the tube of the telescope and can‛t be seen directly. This is the focal point of the objective lens.

4 Ask your friend to hold the paper at the focal point. Face the back side of the paper and look at the image through your magnifying glass. Adjust the position of the magnifying glass until the flashlight image is magnified.

5 Now ask your friend to take the paper away, but continue looking through the eyepiece of your telescope. The image should be a lot brighter since the paper won‛t be diffusing the light.

6 Try looking at other objects that are near the flashlight by slightly moving the eyepiece up, down, and from side to side.


Centre of gravity is the point there all the weight of the object can be considered to be concentrated. Here is an easy way to find the center of gravity of a long, thin object, even if the object‛s weight is unevenly distributed.

You will Need: A meterstick, cane, or any stick

of similar length.

Clay or weight.

Masking tape

Here’s How: 1 First try the experiment with just the stick itself. Then tape the clay or weight somewhere on the stick and try again.

2 Support the stick by resting each of its ends on a finger. Slowly slide your fingers together until they meet. Your fingers will meet under the stick‛s center of gravity. Attach the weight or a piece of clay to some point on the stick. Again support the stick on two fingers, and then slide your fingers together to locate the new center of gravity. Move the weight or piece of clay to some new place on the stick. Repeat the experiment. Your fingers will always meet right under the center of gravity.

What’s going on? The stick‛s center of gravity is the place where you could balance the stick on just one finger. When you first support the stick with two fingers, in general one finger (the one that is closer to the

Center of Gravity


center of gravity) will be holding a little more of the weight than the other. When you try to move your fingers closer together, the one that is carrying less weight will slide more easily. This finger will continue to slide more easily until it gets closer to the center of gravity than the other finger, at which point the situation will reverse and the other finger will begin to slide faster. Your left and right fingers simply alternate moving until they meet at the center of gravity, where both fingers support equal weight.

Classification ‐ Crossword Puzzle Across 5. A vertebrate that has scaly skin. 7. We use this to help us to work out which group a living thing

belongs to. 8. Sorting things into groups 9. Plants make their own food using

energy from this... 10. Plants and animals are divided into

two large groups called... Down 1. This group of vertebrates as

feathers and a beak. 2. An animal that has smooth, moist

skin, and needs air and water... 3. Humans are in this group of

vertebrates. 4. This group of animals has fins 6. Animals with backbones are called...

Center of gravity is a geometric property of any object. Determining the centre of gravity is very important for any flying object like kite, aeroplane, rockets etc.


What do I need? Two identical small, wide-mouthed jars Hot water Cold water Food colouring Scissors Index cards or squares of waxed paper A large, shallow baking pan (if you don‛t

have one, do this activity in the sink—it can be messy).

What do I do? 1 Fill one of the jars with very hot tap water. Add a drop of red food colouring. What happens to the drop? Watch for a minute, then put the red jar into the baking pan sink.

2 Fill the other jar with cold water. Add a drop of blue food colouring. What happens to that drop?

3 Cut a square of 3 inches off the index card or waxed paper.

4 Slowly add more water to the blue jar until you can see a bulge of water over the rim of the jar.

5 Lay the square card carefully onto the top

The Amazing Water Trick Do hot water and cold water mix?

Tips for Home Scientists

This experiment can be tricky-and messy. You may need to practice step 6. Get an adult to help


of the blue jar. Tap the card gently with your finger. (Don‛t poke it. You want the card to be flat and form a seal with the water and the jar.)

6 This part is very tricky. You may want to practice it a few times over the sink with a jar of plain water. Pick up the blue jar and turn it straight upside-down. You don‛t need to put your hand on the card. The water will hold the card in place. (Just flip the jar over. Don‛t hesitate. If the jar is tilted but not turned over completely, the water will gush out and make a mess.)

7 Put the upside-down blue jar right on top of the red jar.

8 Have someone hold onto both jars while you very slowly and carefully pull the card out.

9 What happens? What colour is the water in the top jar? What color is the water in the bottom jar?

10 Empty both jars. Rinse them. Repeat steps 1 through 6—but put the jar with the blue-colored cold water in the baking pan and put the card on top of the jar with the red-colored hot water. Turn the red jar upside-down and put it on top of the blue jar.

11 Slowly pull out the index card. What happens? What colour is the water in the top jar? What color is the water in the bottom jar?

Why does the water mix so quickly when the glass of hot water is on the bottom?

You probably know that some liquids float on top of other liquids


as they are lighter than others. Oil floats on water. Alcohol floats on oil. That‛s because these liquids have different densities. Whenever you put together two liquids that don‛t mix, the liquid that is less dense will float on top of the denser liquid. A drop of oil weighs less than a drop of water the same size. The oil is less dense than the water, so it rises to the top.

When you heat up water, the water molecules start moving around faster and faster. They bounce off each other and move farther apart. Because there‛s more space between the molecules, a volume of hot water has fewer molecules in it and weighs a little bit less than the same volume of cold water. So hot water is less dense than cold water. When you put the two together with the hot water on the bottom, the hot water rises to the top, mixing with the cold water along the way and creating purple water.

Why doesn‛t the water mix when the hot water is on top?

When the cold water is on the bottom, the hot water doesn‛t have to rise—it‛s already on top. The cold blue water stays on the bottom and the hot red water stays on top.

How can I experiment further?

What do you think would happen if you tried this experiment with a jar of salt water on top and a jar of water without salt on the bottom? Try it and see. Use food colouring to colour the salt water a different colour than the plain water so that you can see what happens.


Our world is full of different animals some are so small that we can‛t even see them with naked eyes for e.g. amoeba, paramecium etc. Some are found in deep of sea like starfish, octopus. To see them we need to go at the bottom of sea Our animal world is divided in invertebrates (animals without back bone) and vetebrates (animals with back bone).

Can you name five invertebrates and five veterbrates?

Invertebrates are further divided into 9 phyla which have some characteristic feature. Following are the name of the phyla, their representative animal and the characteristic feature. Match all the three.

Wider World

Crawl on a single fleshy pad.

Have bodies divided into five parts.

Echinoderms

Arthropods

Phyla Representative animal Characteristic feature


Have long thin round worm-like bodies with no segments.

Have flat worm-like bodies.

Have thin sack like bodies with tentacles.

Have bodies made of loosely joined cells.

Annelids

Cnidarians

Poriferans

Platyhelminthes

Have joined legs, a hard covering and their bodies are divided into sections.

Molluscs

Have round worm-like bodies that are divided into segments.

Nematodes


The bonds between the atoms of substances are broken during a chemical reaction. Atoms will, however, form new bonds as they rearrange themselves during the reaction.

Some chemical reactions give off energy in the form of sound, light, or heat. These are called exothermic reactions. Other reactions absorb energy. These are called endothermic reactions.

We used sodium carbonate (Na 2 CO 3 ) and sodium bicarbonate (NaHCO 3 ) as examples of exothermic and endothermic processes. It‛s an easy, no mess experiment.

You will Need Washing Soda (Na 2 CO 3 )

Baking Soda (NaHCO 3 )

Two plastic glasses

100 ml of room temperature water

Spoon

Here’s How: 1 Pour 50 ml of the water into one cup, the other 50 ml in the other cup.

2 Place a spoonful of washing soda in one cup and stir.

Hot and Cold Chemistry


3 Place a spoonful of baking soda in the other cup and stir.

4 Grasp a cup in each hand.

What’s Happening The cup containing the water and washing soda should feel warmer than the cup with water and baking soda. The washing soda-water mixture goes through an exothermic process because the washing soda (sodium carbonate) is ionized—it shares electrons with the water. The baking soda/ water mixture is probably weakly endothermic but may just feel cooler relative to the other mixture.

To create an endothermic process you could use ammonium nitrate with water. That solution will feel cooler to the touch. (Ammonium nitrate is available from some garden stores). Combining salt and ice-water also works.

One common endothermic reaction you don‛t have to create yourself is a lightning strike. In lightning strikes, air is heated and the nitrogen and oxygen combine to form nitric oxide.

AMAZING FACTS l The strongest muscle in the body is the tongue.

l If you yelled for 8 years, 7 months, and 6 days, you would have produced enough sound energy to heat up one cup of coffee.

l The ant can lift 50 times its own weight, can pull 30 times its own weight, and always falls over on its right side when intoxicated.

l A cockroach will live 9 days without its head before it starves to death. Elephants are the only animals that can’t jump. An ostrich’s eye is bigger than its brain.

l Chimpanzees have about the same memory capacity as a preschool age human child. l All polar bears are lefthanded. They are also one of the very few mammals that have hair on the soles

of their feet. l A spider’s web is stronger than steel. A spider’s web would be five times stronger than a piece of steel

of the same size.


Hey you have enjoyed playing with soap bubbles? These fragile spheres of soap film filled with air are both beautiful and captivating. However, few people have observed them closely because soap bubbles are fragile and very light. When you blow soap bubbles out of doors, the slightest breeze carries them away. If you blow them indoors in still air, the bubbles soon settle onto a surface and break. However, because they are very light, soap bubbles will float on a gas that is only slightly more dense than the air that fills them. Such a gas is carbon dioxide. When soap bubbles settle into a container of carbon dioxide, the bubbles float on the carbon dioxide and can be examined closely.

You will need Soap bubble solution A wand for blowing soap bubbles A large transparent container with an open top ½ cup of baking soda (sodium bicarbonate) Vinegar Shallow glass dish to fit inside large container

Here’s how Set the large container on a table away from drafts and

where you can easily look through its sides. Place the glass dish

Floating Soap Bubbles


inside on the bottom of the large transparent container. Put ½ cup of baking soda in the glass dish. Pour 1 cup of vinegar into the dish with the baking soda. The mixture of soda and vinegar will immediately start to fizz as they react and form carbon dioxide gas. Carbon dioxide is more dense than air and so it will be held in the large container as long as it is not disturbed by drafts of air over the container. Because carbon dioxide is colourless, you cannot see it inside the container. However, you will soon be able to detect its presence with soap bubbles.

After the fizzing in the dish has subsided (about a minute), gently blow several soap bubbles over the opening of the large container, so that they settle into the container. This may take a bit of practice. (Do not blow directly into the container, you will blow the carbon dioxide out of it.) When a soap bubble settles into the container it will not sink to the bottom, as it would in air. Instead, it will float on the surface of the invisible carbon dioxide in the container.

While the bubble is floating on the carbon dioxide in the container, you can observe the soap bubble closely. Note what the bubble looks like. What colour is the bubble? Can you see more than one colour on the bubble? Do the colours change? Notice the size of the bubble. Does its size change? Observe the position of the bubble. Does it stay at the same level in the container? Does it rise or sink?

When you have finished observing the bubbles, dispose of the mixture in the glass dish by rinsing it down the drain with water.


What’s going on? The colours of a soap bubble come from reflections of the white light that falls on the bubble. White light, such as from the sun or from a light bulb, contains light of all colours. Light has waves, and the length of the wave, from crest to crest, determines the color of the light. When light reflects from a bubble, some of each wave reflects at the outside surface of the soap film. Some light travels through the soap film, and reflects from the inside surface of the film.

If your soap bubbles remained floating on the carbon dioxide for more than a minute, you may have noticed that the bubbles were slowly becoming larger. You also may have noticed that the bubbles slowly sank into the container. When you blew the bubble, it was filled with air. When it settled into the container of carbon dioxide, the bubble was surrounded by this gas. The bubble grows because carbon dioxide moves into the bubble (through the soap film) faster than air moves out of the bubble. Carbon dioxide can move through the soap film more quickly than air, because it is more soluble in water than is air. (Water is the major component of the bubble-soap solution.) As the amount of carbon dioxide in the bubble increases, the bubble becomes heavier and sinks lower into the carbon dioxide in which it is floating.

start later end CO 2 moves more easily into the bubble than air moves out.


What do I need? A glass jar or clear drinking glass

Vegetable oil

Salt Water

Food colouring (if you want)

DANGER! Don‛t forget to be careful with glass.

1 Pour about 3/4 cup of water into the jar.

2 Pour about 1/3 cup of vegetable oil into the jar. When everything settles, is the oil on top of the water or underneath it?

3 If you want, add one drop of food colouring to the jar. What happens? Is the drop in the oil or in the water? Does the colour spread?

4 Shake salt on top of the oil while you count slowly to 5. Wow! What happens to the food colouring? What happens to the salt?

5 Add more salt to keep the action going for as long as you want.

Salt Volcano


What’s Going On? Why does the oil float on the water?

Oil floats on water because a drop of oil is lighter than a drop of water the same size. Another way of saying this is to say that water is denser than oil. Density is a measurement of how much a given volume of something weighs. Things that are less dense than water will float in water. Things that are more dense than water will sink.

Even though oil and water are both liquids, they are what scientist call immiscible liquids. That‛s a fancy word that means they don‛t mix.

What happens when I pour salt on the oil?

Salt is heavier than water, so when you pour salt on the oil, it sinks to the bottom of the mixture, carrying a blob of oil with it. In the water, the salt starts to dissolve. As it dissolves, the salt releases the oil, which floats back up to the top of the water.

Wow! Didn’t Know That! Lava Lites are lamps that were invented by an English man named Craven Walker in 1964. They are basically tall thin glass jars filled with liquid and a special kind of coloured wax, set on top of a base with a light bulb. When the bulb is turned on, the lamp glows, the liquid heats up, and the wax begins to melt. Blobs of wax rise to the top of the lamp, then cool and sink back down—over and over again.


Chimes are commonly available at gift stores and our homes. But here you are going to produce sound is from simple things, which will remind you of a church bell or chime. Come on, lets do listen ....

What do You need? Scissors

String

Wire hanger

Table (or a wall, or a door)

Metal spoon

1 With your scissors, cut a piece of string about 3 feet long.

2 Hold the two ends of the string in one hand. The rest of the string will make a loop.

3 Lay the loop over the hook part of the hanger. Push the two ends through the loop, and pull them all the way through the other side. (This is easier to undo than a knot.)

Secret Chimes


4 Wrap the loose ends of the string two or three times around the first fingers on each hand.

5 Swing the hanger so it gently bumps against the leg of a table, or against a door. What did it sound like? Probably not much.

6 Now put your hands over the openings of your ears. (Don‛t put your fingers in your ears!) Hold your hands tight to the sides of your head. Lean over and gently bump the hanger again.

7 Wow! Now what does it sound like? Church bells? Chimes?

8 Want to hear what a spoon sounds like? Unwrap your fingers, then pull on the loop end of the string. The whole string will come off the hanger, and you can reloop it around the spoon.

What’s Going On? What‛s going on when you hear a sound?

You hear sounds when vibrations get inside your ears and stimulate your nerves to send electrical signals to your brain.

When you put your hands over your ears, you provide a path that lets more of the vibrations reach your ears. When your hands aren‛t over your ears, you hear a faint, high-pitched, tinny sound. When you put your hands over your ears, you hear deep, resonant, bell-like tones. The hanger makes the same sound in both situations, but in one you provide a path that lets more of the sound reach your ears.


recycle some cans to make a BONGO for great after-dinner music!

Go to your kitchen and check for empty cans like that of condensed milk, tinned fishes; rasgulla cans etc. & collect them. What can you do from these cans? Come lets do and see ...

What do I need? Tin cans (you‛ll need at least 3 cans of the same size Sturdy tape (masking tape is okay, but plastic packing tape or

duct tape works best) Towel Can opener Wooden spoon Pencil

Tips on Cans: Bongos made from cans of different sizes will all sound

different. Try making Bongos from little cans, bigger cans or really big cans. With a set of Bongos, your whole family can make some interesting music together.

Make sure that your cans have flat bottoms that you can cut off with a can opener. Cans with rounded bottoms won‛t work.

1 Ask a grown-up to use the can opener to cut off the bottoms of all of the cans-except one. Leave the bottom on that one. (If you‛re using different sizes of cans, make sure one can of each size has a bottom.)

2 Wash the insides of the cans and let them dry. (Be careful of the cut edges: They might be sharp.)

Can Bongo


3 Take a can that still has a bottom and put it on the counter, open end up. Put another can of the same size on top of it. Tape them together.

4 Put the next can on top of the other two, and tape it to them. Now you have a Bongo that‛s three

cans long, with one closed end and one open end. (You can also make a four- or five-can Bongo if you have enough cans.)

5 Put a towel down on your kitchen floor. Hold your Bongo open end up, and bonk it up and down on the towel. Try making different sounds. You

can make your own rhythms by bonking faster or slower, softer or harder. If you hold your hand over the opening as you bonk, does that change the sound?

What’s Going On? Why does a long Bongo make a deeper sound than a short Bongo?

Compare two Bongos that are made of cans of the same size. You‛ll find that the longer Bongo makes a lower-pitched sound than the shorter Bongo.

Every sound begins with a vibration, and a sound‛s frequency is the rate of vibration-the number of times something vibrates in a unit of time. Something that‛s vibrating very fast-like the steam rushing out of a whistling pressure cooker or the metal of a tiny bell-makes a high-pitched, high-frequency sound. Something that is vibrating more slowly-like the drumhead of a bass drum or the metal of a big bell-makes a low-pitched, low-frequency sound.


When air inside a Bongo vibrates, it makes a sound that contains many different frequencies. This complex sound bounces around inside the metal tube. Sometimes vibrations of the same frequency overlap and add together. When that happens, sounds with that frequency get louder. The length of the Bongo helps determine which sounds get louder. Long Bongos amplify low-frequency (low- pitched) sounds; short Bongos amplify high-frequency (high-pitched) sounds.

Make Your Own Barometer Materials Needed:

l Drinking straw (clear plastic). l Narrowneck glass bottle. l A rubber or cork stopper which fits in the neck of the bottle

Instructions 1. Insert a drinking straw into the bottle. 2. Fill the bottle about halfway full

of water. 3. Seal the neck of the bottle around

the straw either with the rubber stopper or a cork.

4. Make sure the end of the straw is immersed in the water and that the water level in the straw is above the top of the bottle.

As the air pressure outside the bottle de creases, the trapped air inside the bottle will push the water up the straw. As the air pressure outside the bottle increases, it will push the water farther down the straw.


Have you ever noticed that when milk and water mix they form a uniform mixture. Similarly when you mix squash in water they also from uniform mixture. But do all liquids, when mix, from uniform mixture? What do you think? Let‛s find out the answer. You will need 1/3 cup light corn syrup 1/3 cup glycerin Funnel 1/3 cup vegetable oil 1 tall, clear glass or jar 4 small glasses Food colouring 1/3cup water Here’s How 1 Pour the corn syrup, glycerin, water, and vegetable oil into four separate cups. 2 Add a few drops of red food colouring to the corn syrup. Add drops of blue to the water. Don‛t colour the oil or glycerin. 3 Pour the red syrup into the glass or jar. Try not to let it dribble down the sides. 4 Use the funnel to pour the glycerin down the inside of the glass. Pour carefully to avoid disturbing the bottom layer. Wash the funnel. 5 Repeat step 4, first adding the blue water, then the oil, washing the funnel between steps. The liquids will stay in separate layers if you are careful not to shake the glass. Why? Each liquid has its own density. You added liquids in order from highest to lowest density. The oil stays on top because it is least dense.

Layered Liquids


Adaptation Plants survive in their surroundings

Because they adapt To conditions that are found in

The desert habitat. There it‛s always hot and sunny

The air is very dry Soil is sandy and it‛s rocky

And the winds go blowing by. How have desert plants adapted

To their habitat? Roots are long for finding water

That they store in stems so fat. Leaves lose water so they‛re smaller

Some plants have none, you know Cacti have spines that will protect them.

Other kinds of plants are living Where they must adapt

To the tropical rain forest a wet, shady habitat.

There it‛s always warm and rainy Soil is shallow and poor

There‛s so many plants it‛s shady On the forest floor.

In the tropical rain forest How do plants adapt

Buttresses support the tall trees Drip-tip leaves shed water.

Prop and stilt roots can be found here— Supporting while they feed.

Some plants climb or live on others For the light they need.


When you were small all of you have played with toys, cars etc. bought from market, some of these produced lights, some used to produce different sounds. But here you are going to make a fantastic toy with easily available things that shimmers when you shake it ! Come fast, lets make it.

You will need Rubbing (isopropyl) alcohol

Vegetable oil

A plastic container or glass jar with an interesting shape

Small beads, sequins, glitter, or other tiny, shiny things

Food colouring (if you want)

Clear tape (if you want)

DANGER!

Don‛t forget to be careful with glass.

Here’s How 1 Fill about 1/4 of the jar with rubbing alcohol. Add a drop of food colouring.

Glittering Liquids


2 Pour vegetable oil into the jar. Leave about 1/2 an inch of air at the top of the jar. Let the globs of oil settle. Is the oil on top of the alcohol or underneath it?

3 Drop tiny, shiny things into the jar. Use as many as you want. Don‛t use anything too heavy-like a marble-that might break the jar when you shake it.

4 When all the tiny things are in the jar, carefully pour in more oil until the jar is completely full-right up to the rim.

5 Screw the lid of the jar on very tightly. (If you want, you can tape around the lid to make sure it won‛t leak.)

6 Gently shake the jar. The oil and alcohol will mix and turn a milky colour, and the beads and glitter will float and spin.

7 Let the oil settle again. That will take about 5 or 10 minutes. Now spin the jar instead of shaking it. What happens?

What’s Going On? Why doesn‛t the oil float on top of the alcohol?

Since oil floats on top of water, you might have thought that oil would float on top of alcohol, too. But the oil sinks to the bottom and the alcohol floats on top of the oil. Even though water and alcohol are both clear liquids, they have different densities.


Alcohol floats on top of oil because a drop of alcohol is lighter than a drop of oil the same size.

Why don‛t oil and alcohol mix? For that matter, why don‛t oil and water mix?

The answers to these questions have to do with the molecules that make up oil, water, and alcohol. Molecules are made up of atoms, and atoms are made up of positively charged protons, negatively charged electrons, and uncharged neutrons.

The atoms that make up water molecules and alcohol molecules are arranged so that there is more positive charge in one part of the molecule and more negative charge in another part of the molecule. Molecules like this are called polar molecules.

The charged particles in an oil molecule are distributed more or less evenly throughout the molecule. Molecules like this are called nonpolar molecules.

Polar molecules like to stick together. That‛s because positive charges attract negative charges. So the positive part of a polar molecule attracts the negative part of another polar molecule, and the two molecules tend to stay together. When you try to mix water and oil or alcohol and oil, the polar molecules stick together, keeping the oil molecules from getting between them-and the two don‛t mix. When you try to mix water and alcohol, they mix fine, since both are made of polar molecules.


Micro organisms like bacteria are sometimes helpful and sometimes harmful for us. Do you know that the milk we drink also contain bacteria?

In this experiment, you will determine how much bacteria is present in the milk that you drink. It is necessary to find the amount of bacteria present in your milk to make sure that the milk is safe to drink. You can use the “Methylene Blue Test” to determine the amount of bacteria in the milk.

You must be surprised that what is this methylene blue? This is a dye (stain) which colours some substances so that they can be clearly visible under microscope. You might have seen the slides of cheeks cells or onion peel under the microscope in your biology lab, your slide are also made using such stains.

You will Need: Methylene Blue Solution (Ask your science teacher for this

solution) Refrigerated milk Two calibrated test tubes that have rubber stoppers Two medium size glass jars Calibrated (cc) medicine dropper Test tube stand Thermometer Tongs Watch Hot plate Saucepan

Here’s How : Step 1:

Sterilize test tubes to remove any presence of bacteria. You can sterilize the test tubes by boiling water in a saucepan and then use

“Find the Bacteria Hiding In Your Milk”


the tongs to carefully place the test tubes in the boiling water. Next place the rubber stoppers in the boiling water. Let the test tubes and stoppers to boil for one minute.

Step 2:

Carefully put the test tubes in the tube stand. Fill each test tube with 9 cc of refrigerated milk using the medicine dropper.

Step 3:

Drop 1 cc of methylene blue into the first test tube. The first test tube will be the testing sample. Put the stopper on the test tube and shake the test tube until the methylene blue mixes with the milk. Record the time using your watch.

Note:

Add nothing to the second test tube because it will be our control sample. Put a stopper in the second test tube.

Step 4:

It is important to keep both test tubes at a temperature of 37°C To do this, put water in the saucepan and slowly heat it. Pour water into each glass jar until they are 3/4th full. Put the glass jars in the saucepan. Add additional water to the saucepan until the water level in the saucepan is the equal to the glass jars. Use the thermometer to determine when the water is at 37°C.

Step 5:

Put one test tube in each glass jar. Leave the test tubes in the jars and check them every thirty minutes for the first two hours. Then check the test tubes once every sixty minutes. Note the colour of the “test” sample test tube each time to see if the blue


colour is disappearing. You can stop checking once the “test” sample that was blue has turned to the same colour white as the “control” sample.

Make sure to record your results each time.

Use the following information to determine the quality of your milk.

“Excellent Milk” takes over 8 hours to turn white. There are a variable amount of organisms per cc of milk.

“Good Milk” takes 5.5 to 8 hours to turn white. There are under 500,000 organisms per cc of milk.

“Fair Milk” takes 2 to 5.5 hours to turn white. There are approximately 500,000 to 4,000,000 organisms per cc of milk.

“Poor Milk” takes 20 minutes to 2 hours to turn white. There are 4,000,000 to 20,000,000 organisms per cc of milk.

“Very Poor Milk” takes under 20 minutes to turn white. There are over 20,000,000 organisms per cc of milk.

Summary of Results: Quality of milk is determined by how much bacteria is present in the milk directly after processing.

Bacteria needs oxygen in order to grow.

The Methylene Blue Test tells you how much dissolved oxygen is in your milk sample.

Milk that makes the blue colour disappear the fastest has the most bacteria and therefore is the lowest quality of milk.

class ‐ ix - · pdf file · 2011-08-22eduheal foundation class - ix 3 class ‐...

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