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© John Wiley & Sons Australia, Ltd 1
Topic 1 Science is …
Answers
Think about science
What do scientists do? They study living things and the way they interact with one
another and the world around them, the behaviour of natural and
manufactured things, substances,the Earth and how it changes,
the stars,the sun, the planets, their moons and other heavenly
bodies.
Do people other than scientists use
science in their work or leisure
activities?
Everybody does, no matter where they live or what they do.
How is a science laboratory different
from other rooms?
It contains taps and sinks, gas taps, eye wash, fire blankets, a
broken glass bin and severalother different features,which could
include a fume cupboard.
Is the science laboratory a dangerous
place?
It can be if you are not careful. It is important that rules outlined
by your teacher and displayed in the room are followed for the
safety of everyone in the room.
Am I a good observer? You can find out by completing Investigation 1.4 ‘Are you a
good observer?’
How are substances heated safely in
the science laboratory?
Safety glasses must be worn when any substance is being heated.
Laboratory coats should also be worn. When using a Bunsen
burner, a heatproof mat must be used and the burner must be lit
correctly. Substances in test tubes are heated by moving the base
of the test tube gently in and out of the blue flame. The open end
of the test tube should be pointing away from you and fellow
students. Liquids in a beaker can be heated by placing the beaker
on a gauze mat placed on a tripod.
Your quest
1-3.
Answers will vary but could include a man or a woman wearing a lab coat using scientific equipment
such as a test tube, bunsen burner or a beaker.
4. Answers will vary but could include: investigate, discover, explore, scrutinise, analyse, study,
research.

Chapter 1 Science is … Answers
1.2 Science is … everywhere!
1. Answers will vary. Examples are given.
Occupation Howscience is used
(a) Nurse Measuring blood pressure
(b) Mechanic Using oil to stop parts from wearing too fast
(c) Gardener Adding chemicals to soil to make certain plants grow better
(d) Chef Using a saucepan lid to make something boil faster
(e) Architect Knowing how to design a building that will not collapse under the weight of
the roof
(f) Police officer Doing tests to find out the blood type left on a broken window during a
crime
2. (a) Substances in living things
(b) The natural behaviour of the Earth
(c) The way in which sea creatures interact the environment and between themselves
3. Examples include light switch, toilet, bathroom tap, alarm clock, bicycle, spoon and toaster.
4. (a) A nutritionist might develop an eating program that will provide the right combinations of nutrients
at different stages of the player’s training regimen and performance.
(b) A sports psychologist may help by training the mind for motivation and performance.
(c) A physicist might research the effects of frictional forces on balls, racquets and playing surfaces; they
may also examine the effects of different materials for use in racquets.
5. Student responses will vary but should include at least five questions for the interview. Examples of
questions may include:
 Why do you choose to go in this career?
 What is the most interesting part of your job?
 What does a day in your life look like?
 If you could have chosen another science to study, what would you have chosen?
 What would you recommend for someone who wanted to follow in your footsteps?
6. CSIRO stands for Commonwealth Scientific and Industrial Research Organisation. It is Australia’s
national science research agency. Scientists at CSIRO work together to find answers for the biggest
challenges using innovative science and technology to shape the future.
7. There are many ways to become an engineer or a scientist. A common pathway would be to complete
subjects such as physics, chemistry and biology at school, then complete a university degree in science
or engineering. Another route would be to volunteer at not-for-profit scientific organisations in order to
gain experience before applying for full-time work.

1.3 The science laboratory
1. (a) To protect benches from heat damage
(b) Porcelain container for evaporating small amounts of substances over a Bunsen burner
(c) Holds test tubes upright
(d) Used with clamps and bossheads to hold equipment at the required height
2. Any three of: Bunsen burner, heatproof mat, tripod, gauze mat, evaporating dish, beaker,test tube,
tongs, test-tube holder, safety glasses and lab coat.
3. To prevent severe damage to the skin should the chemical be spilled
4. Fan the odour from above the mouth of the test tube or beaker to your nose with your hand.
5. The blue flame is the hotter Bunsen flame.
6. Tell your teacher immediately.
7. (a) Test-tube holder
(b) Measuring cylinder
(c) Spatula
(d) Stirring rod
8. (a) Tasting chemicals, throwing things, touching a power point, sitting on a bench, smelling
contents of test tube, hair not tied back, not wearing safety glasses or lab coats, chemicals spilled on
bench, lid off containers containing poison, paper near flame, matches near flame, pushing other
students, eating food in the lab, filled beaker near the edge of the bench, glassware left in the sink,
being in the lab unsupervised, leaving food on the bench, running in the lab, boxes left on the floor,
dumping glassware and water straight into the sink
(b) In each situation, there is the potential for damage to either the student doing the wrong
thing or their classmates,and for equipment to be broken.
9. (a) Matches cannot be safely washed down the sink.
(b) Never point a test tube towards you when heating, in case the material in it splashes or bubbles
out.
(c) Safety glasses should be worn when heating over any Bunsen burner flame.
(d) Water spills should always be cleaned up because they can be dangerous.
10. Answers will vary. Students should clearly explain the safety rule in their chosen format. An
example would be to create a catchy tune about the importance of wearing safety glasses.

1.4 Detective skills
1. A scientist makes observations, forms hypotheses and comes to conclusions.
1. A hypothesis is an educated guess, while a conclusion is the final outcome of an investigation.
2. All of them.
3. An inference is a suggested explanation about what has happened based on initial observations. A
hypothesis is an educated guess about what happened that can be tested by an experiment, further
observations or measurement.
5. (a) Observation
(b) Observation
(c) Inference
(d) Inference
(e) Observation
(f) Observation or inference — the dog could be playing.
6. Student responses will vary but should be a creative response involving touch, taste and smell. A
suggestion may be for students to start is to list some of the things they expect in a remote forest — the
smell of the trees,the taste of the air and raindrops, the feel of the ground as they touch it.
7. (a) Answers will vary but it is likely that sight would be the most used sense.
(b) Answers will vary but it is likely that sight would be the most used sense.
(c) Other senses used could include sound, smell and touch

1.5 Keeping things under control
8. A variable is a factor that may affect the outcome of an experiment.
9. An independent variable is purposely altered by the researcher; a dependent variable is an outcome or
value that results from the change in the independent variable.
10. By changing only one variable at a time, it is possible to assess the effect of just that one variable on the
outcome. If more than one variable were changed at a time, it would be difficult to determine which of
the variables was responsible for the result obtained.
4. (a) Examples may include: the amount of light received, the amount of water,whether fertiliser is
used, how much fertiliser is used, the species of plant and the purity of the water.
(b) Examples may include: the distance being flown, the airline pricing, whether it is a direct flight or
if there is a stopover and the time of year.
(c) Examples may include: mode of transport, distance to the school, whether there are traffic jams and
what time you are travelling at.
5. (a) Answers will vary but should involve separate trials using a set amount of cleaning product with a
set amount of water and clothes of similar volume and degree of staining.
(b) Answers may include: volume of water,mass/volume of cleaning product, temperature of water,
amount of fabric/clothes, degree of staining of clothes/fabric, length of time washed for and
washing machine used.
(c) The washing powder/liquid used
(d) The results are normally determined qualitatively: that is, by having a look at the washed clothes
when they are dry and seeing how much stain remains. However,students may come up with other
methods.
6. (a) Answers may include: the cups are different sizes, there are different volumes of water in the two
cups, the thermometer is on the bottom of the white cup whereas it is higher in the blue cup, the
cups are different colours and there is only one cup of each type being tested.
(b) Size of cups, colour of cups, volume of water, initial temperature of water,position of thermometer
in water,time intervals at which temperatures are taken
(c) Environmental conditions, as long as they are the same for both cups; time of day when experiment
performed
(d) Answers may vary slightly. An example could include the following.
 Step 1: Collect three stoneware and three glass cups of the same volume and colour.
 Step 2: Add the same volume of hot water to each.
 Step 3: Check that the water is the same temperature in each cup.
 Step 4: Record the temperature every 10 minutes for an hour, making sure that the bulb of the
thermometer is about 2 cm from the bottom of the water each time.
 Step 5: Average the temperature readings for each 10-minute interval for each cup type, and
then graph the average readings over the 1-hour interval.

7. Graph comparing plastic cups
8. Jessie’s cup
9. Approximately 36 °C
10. About 65 minutes
11. Answers will vary. Examples may include:
 What conditions affect the germination of seeds?
 Which conditions lead to the greatest plant growth?
 Which colour cloth is the warmest?
 How can a vase of flowers be kept fresh longer?
 Which brand of paper towel is the most absorbent?
 What affects how quickly objects fall?
 Which brand of batteries lasts the longest?
12. a. Responses will vary but may be similar to below.
1. Mark a point exactly 3 metres in front of the basketball ring
2. Ask 10 students to assist in this task.
3. For the first student, have them have 5 shots at the goal from the marked point with their eyes
open and mark how many they get in.
4. Have this student place an eyepatch over their left eye and have 5 shots again.
5. Repeat with covering the right eye.
6. Repeat steps 3–5 for each student.
7. Record and take an average of results.
b. Independent variable: eyes closed.
Dependent variable: ease of shot.
c. To ensure this was a fair test the following should have been done:
· The same number of shots was taken
· The student was the same distance from the ring
· The same ball was used
· The same shooting style was used with each shot
· The same goal was used
13. Student responses will vary. An example for part (a) is shown.
1. Collect 20 identical tennis balls and check to see they all bounce the same when released from 1
metre. Replace any that do not meet this requirement.
2. Wet 10 balls and leave 10 balls dry.
3. Place a 1 metre ruler vertical from the ground.
4. Have a partner ready to measure the height of the ball.
5. Drop the ball from exactly one metre.

6. Record the height it bounces.
7. Repeat with every other ball and take an average for the wet balls and an average for the dry balls.
1.6 Analysing data
14.
2. (a) The calories are given for different amounts of foods: for example, one slice or one tablespoon.
(b) You would need to convert units such as slice or serving into grams, and give content as ‘Energy
(calories) per 100 grams’.
3. (a)
(b) Apart from sodium chloride, the salts of magnesium are the most abundant in sea water.
4. (a)

(b) Student responses will vary but may include:
Agriculture – watering can
Building – screwdriver handle
Electrical/electronic – wire casing
Furniture and bedding – plastic chairs
Housewares – Tupperware
Marine, toys and leisure – barbie dolls
Packaging and materials handling – bubble-wrap
Transport – car dashboard
Other – pen cases
(c) (i) Answers will vary. Examples include packaging (for example, shopping bags).
(ii) Answers will vary. Examples include paper bags and string bags.

5.
(a) The average mass is higher for males.
(b) 9600 kilojoules
(c) 12 000 kilojoules
1.7 Reporting on investigations
15. Scientists write reports to tell others about their work and allow other scientists to replicate their
experiments to verify results.
2. (a) Discussion
(b) Aim
(c) Results
(d) Method
(e) Conclusion

3.
4. (a) H
(b) F
(c) E
(d) A
(e) G
(f) B
(g) C
(h) D
5. Examples of advantages include:
 spreadsheets are easily edited and the information manipulated to change the order of the entries
 information in the spreadsheet can easily be used to produce graphs and charts by pressing just a few
buttons
 an offsite copy of a spreadsheet can easily be made for safekeeping
 spreadsheets can be incorporated into a blog so that a hard copy of the data is not necessary for data
sharing.
Examples of disadvantages may include:
 at least a basic knowledge of how to use a computer spreadsheet is required
 access to a computer is needed
 the computer must have a spreadsheet program installed.
6.
Aim: To observe how the temperature of water changes while it is heated over a Bunsen burner
Hypothesis: If a sample of water is heated from room temperature to boiling by a constant heat source then
the results graphed, the graph will be a straight line.

Materials:
 100 mL measuring cylinder
 Bunsen burner
 matches
 gauze mat
 safety glasses
 retort stand, bosshead and clamp
 thermometer or data logger and temperature sensor
 250 mL beaker
 heatproof mat
 tripod
 stopwatch
Method and results:
1-2. Examples of results are shown below. These will vary depending on factors such as the initial
temperature,the Bunsen burner used and the room temperature.
3-4.
Discuss and explain:
Time (min) Temp (°C) Time (min) Temp (°C)
0 12.5 6 60.5
1 20.5 7 68.5
2 28.5 8 76.5
3 36.5 9 84.5
4 44.5 10 92.5
5 52.5

5. The thermometer does not instantaneously show the temperature of the water — time must be
allowed for the thermometer to rise or fall to the same temperature as the starting temperature of the
water. If you did not wait, the temperature of the water would go either up or down depending on the
original temperature of the beaker and this would give misleading results.
6. The temperature increases fairly regularly until it nears the 90 °C mark. At this point, the temperature
increases more slowly. When the temperature gets to around the 100 °C mark, it will stop rising.
7. Answers will vary. However,in similar conditions, students should have similar results.
8. Answers will vary according to whether the water has begun to boil by the 10-minute mark. If it has
reached boiling point, students may suggest that the water will remain at its boiling temperature for
the next two minutes. If the water has not yet boiled, students may estimate a temperature rise.
Conclusion:
When a 100 mL sample of water is heated from room temperature to boiling by a constant heat source and
the results are graphed, the graph is a straight line. This supports the hypothesis of the investigation.
7.

8. A hypothesis is an educated guess about what might happen in an experiment.
9. Student responses will vary but should include the independent, dependent and controlled variables,
along with an aim, hypothesis, material used, method, result (observation table) and conclusion. An
example of a method is as follows:
1. Collect four 250 mL beakers,each with 150 mL of water.
2. In two of the beakers, add 20 grams of salt. Stir until dissolved.
3. Set up a heatproof mat, Bunsen burner, tripod and gauze mat. Place a thermometer in the beaker and
record the temperature.
4. Turn the Bunsen burner on. While on the yellow flame, place the first beaker on the tripod.
5. Turn to the blue flame and start a timer- record the temperature every 30 seconds for 8 minutes.
6. Repeat with the other beakers.
7. Compare the temperature change in the beakers with salt and those without salt.
10. Table and graph will be generated using a spreadsheet.
11. (a) The experiment ran for 10 minutes.
(b) Initial water temperature = 12 °C
(c) The boiling temperature of water is 100 °C. As the temperature reached 98 °C at 10 minutes, the
time taken for the water to boil would be greater than 10 minutes.
(d) Number of readings taken = 11.
(e) The graph would form a smooth curve until the temperature reaches 100 °C, and then continue as a
straight line with a gradient of zero.
(f) If only 50 mL of water was heated,the time taken for the water to boil would halve if the energy
provided by the Bunsen burner was the same as that provided for 100 mL of water.

(g)
12. Student responses will vary for parts a–d but are unlikely to show a relationship between foot length and
height. However,the prediction of height is better in case of females in comparison to males.

1.9 Review
1. (a) Physicist — C
(b) Chemist — D
(c) Biologist — B
(d) Astronomer — E
(e) Earth scientist — A
2. (a) A seismologist studies earthquakes.
(b) A biochemist studies the chemicals in living things.
(c)An entomologist studies insects.
(d) A botanist studies plants.
(e) A zoologist studies animals.
(f) A vulcanologist studies volcanoes.
3. Seismologists and vulcanologists could be correctly described as geologists.
4.
Wear safety glasses while mixing chemicals. Do
Pour all substances down the sink when finished with them. Don’t
Run in the science laboratory. Don’t
Drink water from the taps in the science laboratory. Don’t
Tie long hair back before using a Bunsen burner. Do
Wait until the end of the lesson to tell your teacher that you have burnt yourself. Don’t
5. Heatproof mat, Bunsen burner, tripod, gauze mat, beaker, matches. Diagrams will vary but should be
similar to the provided example.
6.

7. (a) When lighting a Bunsen burner, light the match before turning on the gas.
(b) When using a thermometer to measure the temperature of a liquid as it is heated, place the
bulb of the thermometer near the centre of the beaker.
(c) When heating a test tube, hold the test tube using a test-tube holder at the top of the test tube
and move it back and forth over the flame.
8. Answers will vary. The storyboards should clearly show the process used to light a Bunsen burner.
9. (a) Conical flask
(b) Evaporating dish
(c) Test-tube holder
(d) Test-tube rack
(e) Bosshead
(f) Stirring rod
10. (a) A front window was broken, clothes were scattered all over the floor, drawers were open and
some blood was on the broken glass.
(b) Glenn
(c) Someone had thrown a ball through the window. It was suggested because the window was
broken.
(d) The house had been burgled.
(e) The house owner had to find an item of clothing very quickly for an important reason,
became frustrated and accidently broke the window in the rush.
11. (a) Thermometer
(b) Beam balance
(c) Measuring cylinder
12. (a) 76 °C

(b) 16.3 °C
13. (a) 24 cm
(b) Between the 0- and 1-minute marks, and between the 4- and 5-minute marks
(c) It moved back towards the starting point.
(d) Due to the slow speed, changes in motion were virtually instantaneous.
14. D
15. A
16. Answers will vary but could include the following:
Independent variable: type of candle used
Dependent variable: number of mosquitoes observed or number of mosquito bites on Luke
Controlled variables: time of night candle is burned, length of time candle is burned for, same
method used to count mosquitoes/bites, same bait, size of the candle, location of candle, similar time
of year/season, distance of candle from location where mosquitoes are sampled
Possible control: a plain unscented candle
17. (a) Amount of light
(b) Plant height and number of healthy leaves
(c) Exposure to wind and rain
(d) Answers will vary. Examples include: they needed to place all of the plants in the same area
to ensure that all of them received the same shelter from wind and rain; they could also have used
many more plants.
(e) Student reasoning will vary but may include any of the variables that should have been
controlled.
18. (a) (b) Answers will vary but could include a person conducting an experiment with independent,
dependent and controlled variables.
(c) Answers will vary however students will hopefully have a clearer understanding of the type of
work a scientist undertakes.

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