NAME:_____________ TEACHERS: ___________ HOUSE: _____

Investigating

@ Dandenong High School

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This booklet is based on a resource from the North Haddersfield Trust School, UK, sourced from TES teaching resources

LABORATORY RULES

Report any accident or breakage to your teacher immediately.1. Only enter a lab when told to do so by a teacher. Never rush about or

throw things in the lab. Keep your bench and floor area clear, with bags and coats well out of the way.

2. Follow instructions precisely; check bottle labels carefully and keep tops on bottles except when pouring liquids from them; only touch or use equipment and materials when told to do so by a teacher; never remove anything from the lab without permission.

3. Wear eye protection when told to do so and keep it on from the very start until all practical work is finished and cleared away.

4. When using naked flames (eg, Bunsen or spirit burners or candles), make sure that ties, hair, baggy clothing etc are tied back or tucked away.

5. Always stand up when working with hazardous substances or when heating things so you can quickly move out of the way if you need to.

6. Never taste anything or put anything in your mouth in the laboratory. If you get something in your mouth, spit it out at once and wash your mouth out with lots of water. Tell your teacher.

7. Always wash your hands carefully after handling chemicals, microbes or animal and plant material.

8. If you are burnt or a chemical splashes on your skin, wash the affected part at once with lots of water. Tell your teacher.

9. Never put waste solids in the sink. Put them in the bin unless your teacher instructs you otherwise.

10.Wipe up all small spills and report bigger ones to your teacher.

I confirm that I have read through and understood the laboratory rules at DHS.

Sign: …………………….

Date: …………………….

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Safety You will usually find a set of ‘Lab Rules’ in a science lab. They are there for your safety!

The drawing below shows a lab where there are no safety rules.

1. Highlight or circle all the hazards / things going wrong in this lab.2. Write them in the left-hand column of the table on the next page.3. Explain why each action is a hazard in the middle column.4. Explain what should be done instead in the right-hand column.

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HAZARD WHY IS IT DANGEROUS? (RISK) WHAT SHOULD BE DONE INSTEAD? (CONTROL)

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Safety symbolsMany things around a lab have special signs on them warning you of danger.

TASK: Match the symbol to its correct definition. For example, 1 – A

1.Explosive

A. This symbol means that a substance is self-reactive and can explode if not handled correctly.

2.Harmful or Irritant

B. This symbol reminds you to wash your hands after you have done an experiment.

3.Corrosive

C. This symbol means that a chemical is poisonous. Poisons can kill.

4.Highly flammable

D. This symbol means that there is some type of living thing in an area which may make you ill.

5.Environmental danger

E. This symbol reminds you to wear safety glasses or goggles when working in a certain area or using particular pieces of equipment or chemicals.

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6.Toxic

F. This symbol tells you that a chemical will attack your skin if you get it on you.

7.Biohazard

G. Will cause electric shock if handled incorrectly.

8.Eye protection must be worn

H. This symbol warns you that a chemical will catch fire easily.

9.Wash your hands

10.

Electric shock

I. This symbol means that if used wrongly, it could cause harm to the aquatic environment.

J. This symbol warns that a chemical may harm your health if you do not use it properly. The word ‘irritant’ means that the chemical may give you a rash if you get it on you or make you choke if you breathe it in.

Symbol Definition Symbol Definition

1 5

2 6

3 7

4 8

9 10

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Drawing apparatus and glasswareUsually in science we draw diagrams of apparatus rather than pictures. Diagrams are easier to draw, and make it easier to see how the apparatus is joined together.

Imagine that you could cut the apparatus in half. You draw what you would see when you look at the edge – this is called a cross-section diagram.

TASK 1: Draw the diagrams for the missing pieces of apparatus.

TASK 2: Write out the names of each apparatus and match up to their correct use.

Apparatus Name Diagram What it is used for

Test tube Measuring volumes of liquid

Bunsen burner Supporting a beaker or flask and spreading the heat from the flame

Beaker Storing or mixing solids and liquids

Conical flask (i.e. cone-shaped)

Heating a beaker, flask or crucible over a Bunsen burner

Gauze Holding and mixing liquids

Measuring cylinder Evaporating the water from a solution

Tripod Holding liquids or solids

Filter funnel (with paper) Heating things

Evaporating basin Separating an insoluble solid from a liquid

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ObservationsLooking out for things and describing things in detail are two very important skills for a scientist.

Spotting thingsLook at the two pictures below. In Picture B the scientist is not being very careful. There are four things that he is doing wrong. Circle each one on Picture B and write a short explanation about each one on the lines below.

Mistake 1 ____________________________________________________________________

Mistake 2 ____________________________________________________________________

Mistake 3 ____________________________________________________________________

Mistake 4 ____________________________________________________________________

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Describing your observationsWhen you observe things you must make sure that you write down a careful description. If you are using chemicals you need to say:

• Is it a liquid, solid or gas?• What colour is it?• Is it see-through? Transparent is the word for this.

Things you can’t see through are opaque.• If it is a liquid, are there some bits floating in it? Is it cloudy? Cloudy liquids are called

suspensions.

1 Use some of the words above to describe the following substances.a water _________________________________________________________________b salt ___________________________________________________________________c muddy water ___________________________________________________________d cardboard ______________________________________________________________ e glass __________________________________________________________________

2 How would you describe this ant to someone who could not see it?

___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

3 Make a list of similarities and differences between you and a mouse._____________________________________________________________________________________________________________________________________________________________________________________________________________________

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4 You don’t always observe things with your eyes! What about your other senses? You hear things, smell things, taste things and feel things. Scientists need to use all their senses.

a Describe what eating an apple feels, tastes and sounds like._____________________________________________________________________________________________________________________________________________________________________________________________________________

b Shut your eyes and describe all the sounds that you can hear.____________________________________________________________________________________________________________________________________________

Observations give us information as to what is happening in the world around us, or in an experiment. Although scientists use all of their five senses to make observations, sight is probably the sense that gives them the most information. Scientists make either qualitative or quantitative observations.

Qualitative observations are descriptive. They are recorded as diagrams or written down in words. Eg, the colour of a bird’s feathers is a qualitative observation.

Describing a day as hot (a qualitative observation) doesn't really give an idea of how hot it is! A number (measurement) tells us exactly how hot or cold it is. Eg, 43°C. Measurements like this are quantitative observations. They are written as numbers and allow scientists to be more detailed and accurate in their observations.

Activity: List some examples of quantitative and qualitative observations in the table below

Qualitative Observations Quantitative Observations

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Units of measurementUnits of measurement

Units are important! It is no use telling someone that it took 20 to boil some water. Do you mean 20 seconds, 20 minutes or 20 hours?

Whenever you measure something in science, you need to know what the units of measurement are. You then need to write the unit symbol next to the number. Eg. 10 centimetres = 10cm

STARTER: Complete the spaces in the table belowQuantity being measured Name of unit Symbol

length metre mmass kg

second sforce newton

temperature °Cspeed metres per second

square metres m2

volume cubic metres

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Learn and practice: In the boxes below, state the measurements for each of the apparatus.

*Remember to include the units!

Volume

Mass

= =

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= = = = =

= =

How to light a Bunsen burner

The Bunsen burnerThe Bunsen burner is used to heat things in the laboratory.

TASK: Name the parts of the diagram and explain what each part does.

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Remember that a Bunsen burner will get hot when it is used, so never take one apart unless you are told to do so by your teacher. Always let a Bunsen burner cool down before you put it away.

How to light a Bunsen burnerEvery time you use a Bunsen burner, you should follow these steps:

1 Check the hose for breaks and holes. DO NOT use the Bunsen burner if you find any breaks or holes. Give it to your teacher.

2 Connect the hose to the gas tap but do not turn it on yet.3 Check that the air-hole in the collar of the Bunsen burner is CLOSED.4 Light a match and hold it a little distance (about 2 cm) above the top of the chimney of

the Bunsen burner.5 Turn on the gas at the gas tap.6 The Bunsen burner will now light and give you a yellow flame.7 Turn down the gas supply at the gas tap until you have the size of flame needed for

your experiment.8 IF YOUR BUNSEN BURNER GOES OUT, TURN OFF THE GAS AT THE GAS

TAP STRAIGHT AWAY.

Bunsen burner flamesThe Bunsen burner will give three different types of flame: Draw a diagram of the flame above each Bunsen below.

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Roaring flame:

• air hole open, so lots of air mixes with the gas• noisy, blue flame• very hot flame• used for heating things quickly

Medium flame:

• air hole half-open, so some air mixes with the gas• light blue flame, which is quieter than the roaring flame• flame is quite hot• used for heating liquids

Safety flame:

• air hole closed, so hardly any air mixes with the gas• quiet, bright yellow flame• Flame is not as hot as the medium flame• not used for heating, because the flame leaves a layer of soot on

things

If you are not using your Bunsen burner, you should either turn it off,

or close the air hole so that people can see the flame.

Lesson 6 – Drawing bar charts and line graphs.

Bar chartsBreakfast

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You have done a survey to show what the people in your class had for breakfast, and these are your results:

Food Number of peopleCereal 15Toast 7Chips or chocolate 2Nothing 6

You would draw a bar chart like this one to show your results:

1 Draw bar charts to show the results of these surveys.a) Number of plants in a lawn

Plant Number

Daisy 10

Buttercup 7

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Clover 20

Thistle 2

b) Hair colour in a class

Colour Number of people

Black 12

Brown 10

Blonde 8

Red 1

2 Carry out your own survey to find out the following information. Record your results in the tables below and draw bar charts to show your results on graph paper.

a) How the students in your class get to school.b) How many brothers and sisters each student in your class has.

a)

Method of transport Number of people

b)

Student Number of siblingsBrothers Sisters

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Peer assessment

Drawing bar charts

Student’s name:

Peer assessor’s name:

Use the success criteria below to assess your peer’s line graph. Award 1 mark for each criteria met.

Criteria Description MarkPresentation A sharp pencil and ruler is used to draw.Axes The independent variable is along the x axis and the dependent

variable is up the y axis.Axes The axes are both labelled clearly.Axes The units are shown clearly on both axes.Scales The graph fills at least 2/3rds of the space available.Scales The scales are evenly spread along the axes.Points / plots All points are plotted accurately to within +/- 1 mm.Title The graph has an appropriate title that is underlined.Bars All bars are the same width apart.

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WWW (What Went Well): What has the student done well on their line graph?

SCORE

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EBI (Even Better If): How could your peer improve their line graph next time?

Line graphs

Here are the results of an experiment to find out how long a spring is when different forces are applied to it.

Force (N) Length (cm)

0 5

1 10

2 15

3 21

4 26

5 32

6 36

7 41

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Working out the scaleFirst, look at your table of results and work out the largest number that has to go on each axis.

Now count the squares on your graph paper. If there are not enough, try again, counting in 2s, or 5s, or 10s, until you find a scale that fits on the paper.

Two sets of resultsSometimes you might want to put two sets of results on your graph so that you can compare them.

This table shows the temperature inside two cars that were parked in the sun.

Time (hours)Temperature (ºC)

Black car White car

0 15 15

1 20 19

2 25 23

3 30 27

4 35 31

5 40 35

You can draw the two lines in different colours, or use different symbols for the points. Put a key on your graph.

2 Plot a graph, on the graph paper given to you, showing the temperatures inside the cars. Don’t forget to put a title on your graph.

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Student’s name: _____________________________________________________________

Peer assessor’s name: ________________________________________________________

Use the success criteria below to assess your peer’s line graph. Award 1 mark for each criteria met.

Criteria Description MarkPresentation A sharp pencil and ruler is used to draw lines and plot all pointsAxes The independent variable is along the x axis and the dependent

variable is up the y axis.Axes The axes are both labelled clearly.Axes The units are shown clearly on both axes.Scales The graph fills at least 2/3rds of the space available.Scales The scales are evenly spread along the axes.Points / plots All points are plotted accurately to within +/- 1 mm and are a

small dot or cross.Title The graph has an appropriate title that is underlined.Line of best fit A single fine line of best fir has been drawn. (Straight line or a

curve)

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Peer assessment

Drawing Line graphs

WWW (What Went Well): What has the student done well on their line graph?

SCORE

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EBI (Even Better If): How could your peer improve their line graph next time?

Lesson 7 – Heating water

Recording and communicating results.

Safety rules• Never put a thermometer down where someone can knock it off the bench.• Make sure your thermometer has a safety ring fitted.• If you break a thermometer, ALWAYS tell your teacher. Do not try to clear it up

yourself.

TASK: Set up your equipment as shown in the diagram above. Record the temperature of the water every minute for 10 minutes.

Time (min) Temperature (°C)12345678910

TASK: Plot a graph displaying the data collected.

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