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Name ____________________________________________________ Date _________________Physical Science Mrs. Hanna
Compounds
__________________________ : has the same composition and properties throughout
___________________________ : a substance whose smallest unit is made up of atoms of more than one element
Ex. # of elements # of atoms
1)NaCl _________ _________
2)Fe2O3 _________ _________
3)Ba(OH)2 _________ _________
4)Al2(SO4)3 _________ _________
Usually have properties that are ________________________
from the elements that make them up.
Ex. H2O = Water
- Hydrogen and Oxygen are both___________________. Water is a __________________________
Ex. H2O2 = Hydrogen peroxide
- Water is _________________________________ liquid use for bathing, drinking and cooking.
- Hydrogen peroxide has warning labels to keep ____________________________
Mixtures
Mixture : Two or more _____________________________(elements or compounds) come together but don’t combine
to make a new substance (_____________________________________)
Ex.
Traits Mixtures Compounds
Make up:
Combined how?
Can separate by:
Final product:
Types of Mixtures
1)___________________________________________ : contains two or more substances that are evenly mixed together
but not chemically bonded together
Ex.
2)______________________________________: the substances are not mixed evenly
- The different areas of heterogeneous mixtures have different ______________________________and is easy to tell
apart usually.
Ex.
Do How to Separate Mixtures Activity
Separating Mixtures
You can use a ___________________________to separate a mixture of solids.
Examples:
1)How do you separate: Sugar from Sand (fast)
2)How can you separate: Sand, iron filings and salt?
Physical properties vs Chemical propertiesPhysical Property: any characteristic of matter that can be ___________________________(you see) without changing the identity of the materialExamples:1) _______________________________________
2) _______________________________________
3) _______________________________________
4) _______________________________________
5) _______________________________________
Chemical Property: a characteristic of matter that allows it to change to a different type of matter.Examples:
1) ________________________________________________________________________________________________2) ________________________________________________________________________________________________3) ________________________________________________________________________________________________4) ________________________________________________________________________________________________
Physical Change: any change in size, shape, form, or state where the _______________________of the matter stays the
_________________________.
Examples:1) ________________________________________________________________________________________________2) ________________________________________________________________________________________________3) ________________________________________________________________________________________________4) ________________________________________________________________________________________________
Chemical Change: occurs when one type of matter changes into a ________________________________of matter with different properties.Examples:1) ________________________________________________________________________________________________
2) ________________________________________________________________________________________________
3) ________________________________________________________________________________________________
4) ________________________________________________________________________________________________
5) ________________________________________________________________________________________________
6) ________________________________________________________________________________________________
Acids and Bases
Whether a solution is acidic or basic can be measured on the _______________________________.
When ___________________________________________is added to a solution, the color change can indicate the
approximate pH of the solution.
Acids cause universal indicator solution to change from _______________________toward ___________________.
Bases cause universal indicator to change from ________________________ toward _______________________
Acids
An acid is a solution that has an excess of __________ ions. It comes from the Latin word acidus that means "sharp" or
"sour".
The _________________________ions, the ___________________________the solution.
Ex.
Properties of an Acid
Tastes _________________________
Conducts _______________________________
_______________________________ , which means they break down certain
substances. Many acids can corrode fabric, skin, and paper
Some acids react strongly with __________________________________
Turns litmus paper __________________
Uses of Acids
Acetic Acid = _____________________________
Citric Acid =___________________________________________. It is in many sour
candies such as lemonhead & sour patch.
Ascorbic acid = _________________________which your body needs to function.
_______________________________________ is used in the production of fertilizers,
steel, paints, and plastics.
Car ________________________________
Bases
A base is a solution that has an excess of _________________________________.
Another word for base is ____________________________.
Bases are substances that can _________________________ hydrogen ions
Ex.
Properties of a Base
Feels ____________________________
Taste ____________________________
___________________________
Can conduct______________________________. (Think alkaline batteries.)
Do not react with____________________________.
Turns litmus paper ______________________
Uses of Bases
Bases give _______________________, ammonia, and many other cleaning products some of their useful properties.
The OH- ions interact strongly with certain substances, such as ____________________________________________.
Chalk and oven cleaner are examples of familiar products that contain bases.
Your ___________________________ is a basic solution
pH Scale
pH is a measure of how _________________________________________a solution is.
•The pH scale ranges from ___________________________.
Acidic solutions have pH values __________________________________
A solution with a pH of 0 is ___________________________________.
A solution with a pH of 7 is ______________________________.
•Pure water has a pH of 7.
•Basic solutions have pH values _______________________________.
•A solution with a pH of 14 is ___________________________________
A change of 1 pH unit represents a ___________________________ change in the acidity of the solution.
For example, if one solution has a pH of 1 and a second solution has a pH of 2, the first solution is not twice as acidic as
the second—it is __________________________________more acidic.
Acid – Base Reactions
A reaction between an acid and a base is called ________________________________.
An acid-base mixture ________________________as acidic or basic as the individual starting solutions.
When an acid is mixed with a base it produces ______________________
:Solution: a ______________________________ mixture; two or more different substances
are mixed evenly together
Two parts of a solution:
1)______________________________: is the substance that does the dissolving
2) ______________________________: is the substance that is dissolved
Examples:
Coffee: solventà ___________________ soluteà _________________________________
Pepsi: solvent à ______________________ solute à ____________________________________________________
Types of Solutions:
1)Liquid/ solid solution.
Ex. Kool-Aid à
2) Liquid/Liquid solution
Ex. Salad dressing à
3) Liquid/gas
Ex. Soda à
4) Solid/solid (metals = alloy)
Ex. Steel à
Ex. Brass à
5) Gas/gas
Ex. Air à
Universal Solvent: is ___________________________
Why??
The polarity of water molecules enables water to dissolve many
_________________________________ substances.
A positive and negative ion attract each other and form an
__________________________________.
- Water has a positive end (___________________________) and a negative end (_________________________) which
makes it polar
Do: What dissolves better Activity
Problem: What dissolves salt better; water or alcohol?
Hypothesis: _____________________________________________________________________________________
_______________________________________________________________________________________________
_______________________________________________________________________________________________
Procedure
1) In separate c ups, measure two samples of salt that weigh 5 g each.2)Place 15 mL of water and alcohol into separate cups.3)At the same time, add the water and alcohol to the samples of salt.4) Swirl both cups the same way for about 20 seconds and check for the amount of salt dissolved.5)Swirl for another 20 seconds and check. Swirl for the last 20 seconds and check.6) Carefully pour off the water and alcohol from the cups and compare the amount of undissolved salt left in each cup.
For a liquid to dissolve a solid, the molecules of the liquid and solid must attract one
another
1) Is alcohol just as good, better, or worse than water at dissolving salt?
2) How do you know?
Salt (sodium chloride) is made from _____________________________ sodium ions bonded to
____________________________ chloride ions
Water can dissolve salt because the positive part of water molecules ______________________________ the negative
chloride ions and the negative part of water molecules ____________________________ the positive sodium ions.
Why does water dissolves more salt than alcohol?
Isopropyl Water
Alcohol
Do all ionic substances dissolve in water? How do you know?
Procedure1. Label two clear plastic cups Sodium Carbonate and Calcium Carbonate.2. Measure 2 g each of sodium carbonate and calcium carbonate and put them in their labeled cups.3. Measure 15 mL of water into each of two empty cups.4. At the same time, pour the water into the sodium carbonate and calcium carbonate cups.5. Gently swirl both cups.1)What do you observe?
2)) Why doesn’t calcium carbonate dissolve?
3) What is Calcium Carbonate used for?
4) Identify both solutions as either Mixture (heterogeneous) or solution.
Do Mini lab-What dissolves better
Rate of SolubilityWhat can increase the rate of solubility?
1) _________________________________________________________________
Adding energy ( heating) __________________________ molecular motion.
Increased molecular motion competes with the ____________________________ between solute
molecules and tends to make them come apart more easily.
Increased molecular motion causes more solvent molecules to _______________________ solute
molecules and pull on them with more force, usually resulting in more dissolving.
Since different substances are made from different atoms, ions, or molecules, increased temperature will
affect their dissolving to ______________________________________
Solubility curve
Notice that temperature affects substances _____________________________.
How does an increase in temp. affect salt (NaCl)’s solubility?
1)Determine the number of grams of sugar that will dissolve in 100 grams of water at 25°C? _______
2)At 65 °C? ________
Temperature and solubility
Unlike liquid-solid solutions, an increase in temperature __________________________________ the solubility of a
gas in a liquid-gas solution
Carbon dioxide is less soluble in a _________________________________________
Ex. A warm soda will bubble a whole lot more than cold chilled soda
Rate of Solubility
Solubility does not tell you how ___________________ a solute will dissolve à it tells you
only _________________________ of a solute will dissolve at a given temperature.
Some solutes dissolve ____________________________ than others.
By increasing the ____________________________ of solute that comes in contact with
the solvent will increase the rate of solubility.
What can increase the rate of solubility?
1) Increasing the temperature of the solvent
2) _________________________________________________
Increases molecule movement and breaks down the attraction between the solute
3) __________________________________________________
The solvent will be able to act upon more of the solute at one time
Concentration
Concentration of a solution: tells you how much ________________________ is present compared to the amount of
solvent.
Saturated/concentrated: A solution that contains all of the ____________________________ that it can hold under the
given conditions.
Unsaturated/Dilute: Can __________________________________________solute
A ___________________ solution will hold more solute than a _________________________ one. When you cool a
solution some solute will “fall out”
Supersaturated: contains ____________________________________the normal amount of solute
Chemical Reactions
_________________________________________________: shows the reactants, products and proportions of each
substance.
__________________________________: the substances that exist before the reaction begins
__________________________________: The substances that form as a result of the reaction
In a chemical reaction, only the atoms present in the reactants can end up in the products. No
______________________________are created, and no atoms are destroyed.
Reactants Products
Baking Soda + Vinegar
Charcoal + Oxygen
Iron + Oxygen + Water
Silver + Hydrogen sulfide
Gas (Kitchen range) + Oxygen
Sliced apple + Oxygen
Signs of a chemical reaction
1)Something _____________________is made
2)Formation of a __________________________________________________
3)Release or absorption of _____________________________ in the form of light, heat, or
sound
ex.
4)Sometimes a __________________________________________
Something new is made.
In a chemical reaction, only the atoms present in the reactants can end up in the ______________________________.
_________________________ is conserved in a chemical reaction.
Teacher DemoYou will need• Goggles • ½ t Citric acid• ½ t Sodium bicarbonate• ½ t Water•Plastic film canisterProcedure
1. Place ½ t of citric acid in the test tube.2. Use a graduated dropper to add 1 mL of water to the test tube.3. Add ½ t of sodium bicarbonate and quickly place the cover on the canister.4. Hold the test tube straight up. Be sure to point it away from yourself or students
1)What happened?
2) The citric acid and baking soda reacted and made new chemicals. How do you know that something new was made?
3) What type of gas is formed in this reaction?
4) Where do you think the carbon dioxide gas comes from?
Mass must be conserved
Since mass must be _______________________________ each side of the reaction must be balanced.
Ex.
- When a candle burns for a while, it eventually gets smaller and smaller. Where does the candle wax go?
Ex. Paraffin burning Balance the equation of a simple hydrocarbon MethaneWhen the candle was burning, the paraffin reacted with oxygen in the air to produce carbon dioxide and water, similar to the chemical reaction between methane and oxygen
CH4 + O2 à CO2 + H2O Methane Oxygen Carbon dioxide Water
C = C =
H = H =
O = O =
CH4 + O2 à CO2 + H2O
C = C =
H = H =
O = O =
Ex. Silver tarnishing
Ag + H2S à Ag2S + H2
Silver Hydrogen Silver Hydrogen Sulfide Sulfide
Balance the equation
Ag = Ag =
H = H =
S = S =
What do we do?
Ag + H2S à Ag2S + H2
Formation of a gas
Producing a gas can be very useful and being able to _________________________________________produced is
very important.
Ex. Air Bags in car
You will need Reaction bag containing baking soda powder and citric acid pouch or use 10 ml of water and Alka-seltzer tablet in bag Sandwich-sized zip-closing plastic bag (place water and tablet at two ends then mix)
Procedure1. Place the reaction bag inside a sandwich-sized zip-closing plastic bag.2. Remove as much air as possible and seal the outer bag.3. Smack the liquid-filled pouch with your fist or step on it with the heel of your shoe until it breaks.4. Shake the bag to help the reactants combine.
1)What happened?
2) What gas is produced?
3) Is the bag warm, cold are still room temperature?
Do Producing Gas lab
The ions or molecules in two solutions can react to form a _____________________________.
A solid formed from two solutions is called a ____________________________________.
Do forming a white solid DemoMaterials for the Demonstration• Magnesium sulfate (Epsom salt)• Sodium carbonate• Water• 2 clear plastic cups• 1 tablespoon• 1 teaspoon
Procedure:1) Pour 100 mL of water in one clear plastic cup and add 10 g (about 1 tablespoon) of magnesium sulfate. Stir until the solution is clear.2) Pour 50 mL of water in another clear plastic cup and add 5 g (about 1 teaspoon) of sodium carbonate. Stir until the solution is clear.3) Hold up the two clear colorless solutions and slowly pour the smaller amount into the larger
1)What happened?
2) Would you consider adding a sodium carbonate solution to a magnesium sulfate solution a chemical reaction?
3)Why or why not?
Release of Energy
A change in ______________________________is a clue that a chemical reaction may
have occurred.
When the temperature increases during a chemical reaction, it is called an
____________________________________________.
When the temperature decreases during a chemical reaction, it is called an
____________________________________________
It takes energy (__________________________________)to break chemical bonds in the reactants.
Energy is ____________________________________when chemical bonds form in the products.
How does warming or cooling a glow stick affect Its chemical reaction?
Materials for the Demonstration• Hot water in an insulated cup• Ice water in an insulated cup• 2 glow sticksProcedure:1) Be sure not to start the glow sticks as you prepare for the demonstration. 2) Place one glow stick in hot water and another in ice water before students arrive. 3) The glow sticks will need to be in the water for at least a couple of minutes before the demonstration. 4) Remove the glow sticks from both the hot and cold water.5) Have two students bend and start the glow sticks.6) Show students both glow sticks and ask them what they observe. You may pass the sticks around the class so that
they can feel the difference in temperature.
1) How do you start a glow stick?
2) What makes the sticks glow?
3) What difference did you see between the cold and hot stick?
4) What should you do if you want your glow stick to last longer?
5) How can you tell whether the chemical reaction is happening faster or slower in each glow stick?
Color Change
change in color is a clue that a _________________________________ may have occurred.
Universal indicator solution is __________________________ when it has a pH around 7 (neutral).
Acidic solutions have a pH_________________________________.
Basic solutions have a pH _____________________________________________.
Adding a base to an acidic solution makes the solution less
___________________________________.
Adding an acid to a basic solution makes the solution less ________________________________
Color Change DemoProcedure 1) Place a straw in the cup of bromthymol blue indicator solution that you have not yet used.2) Push the straw to the bottom of the cup and gently blow until the solution turns greenish-yellow
1)What gas do you breath out?
2) Why does the solution change color?
3) Knowing this, is the color yellow an indicator of an acid or a base?