This document outlines the template and steps for conducting science experiments, including an aim, hypothesis, method, results, and conclusion. It then provides three sample experiments related to a crime scenario: 1) Measuring vinegar concentration using baking soda, 2) Testing shoe grip to determine if a suspect could climb a hill, and 3) Timing routes between a crime scene and sighting to calculate a suspect's speed. The template ensures experiments are conducted reliably and conclusions drawn based on collected evidence.

1. Template for Science Experiments
These are the steps we use when doing science experiments to ensure fair testing.
Aim: To find out ………
Hypothesis: I think that ……………………….. will happen
Method:
1.
2.
3.
4.
5. Repeat the steps and record the results in the table 2 more times. (Shows
repeatability of the experiment)
Results:
(Time (s)) 0 1 2 3
Measurement
Graph: Usually a line graph if measuring time, distance etc
Conclusion: Usually a rewording of the aim and hypothesis
Discussion: The science as to why things happened or what you would do better next
time.

2. Measuring concentration – Forensics
Possible scenario: A wrapper that had been on some hot chips was found at the scene
that appears to belong to the perpetrators of the crime. They had vinegar on their
chips. The local take-away shops all use different brands on vinegar so if you can
narrow down the type of vinegar you may get a lead from the takeaway shops.
Concentration may be a good way to do this but first you must devise a reliable
method to measure concentration of vinegar.
Part 1
Aim: To measure the concentration of vinegar reliably.
Hypothesis: I think that (the number of spoonfuls of baking soda will help to find the
concentration of vinegar)
Method:
1. Measure exactly 10ml (or 1 tablespoon, or 1 container) of vinegar into a
beaker (or cup) (It will be important to keep the volume of vinegar the same
throughout so you get reliable results)
2. Add 1 teaspoon of baking soda and wait 1 minute
3. Keep adding teaspoons of baking soda 1 at a time until there is no more
reaction. Don’t forget to count the number of teaspoons you add and record it
on the table.
4. wash out all your containers in water and repeat the whole experiment 2 more
times.
Results:
Trial number 1 2 3 Average
Number of
teaspoons
Draw a bar graph of results (not including the average)
Conclusion: Did you get similar results each time you did the experiment? What
could you do to improve your results?
Discussion: The baking soda reacts with the acid in the vinegar. The stronger the
concentration of vinegar then the longer the reaction will go on for and the more
baking soda you will need to add.
Repeat this experiment until you get reliable results.
Further Experiments:
• Change the brands of vinegar (dilute the other brands with water to make sure
you get different results for different brands)
• Change the volumes of vinegar to baking soda (use something smaller than a
teaspoon?) Volumes must be equal!
• Make your own indicator using red cabbage (just boil it up and filter it) and
measure the number of drops of vinegar added to indicator to change its colour
(measuring pH)

3. Experiment 2
Scenario: Some shoe prints were found at the scene of the crime but there were
several different sorts. To get away from the scene of the crime the burglars had to
run up a steep grassy hill in the rain. To do this they would need shoes with good grip.
From the shoe prints at the scene we can identify 2 different types of shoe – a lady’s
smooth soul shoe and a sports type shoe. We need to prove that the lady’s shoe could
not have been worn by the burglars because they do not have enough grip.
Aim: To test the which shoe has the most grip
Hypothesis: I think that the burglars wore the sport shoes because they would not be
able to get up the hill in the lady’s shoes.
Method:
1. Take a piece of board and put the lady’s shoe on one end.
2. Raise the other end of board until the shoe slips
3. Measure the height of the board when the shoe started to slip and record in the
table.
4. repeat with the lady’s shoe 2 more times
5. repeat with the sport shoe 3 times
Results:
Shoe type Trial 1 Trials 2 Trial 3 Average
Lady’s shoe
Sport shoe
Conclusion: The shoe with the most grip was ………. Therefore the burglar could not
have worn the ………… shoe
Shoes with tread have more grip than shoes with no tread. Tread increases the friction
between the sole and the ground, reducing slippage.
Possible further experiments:
• different types of shoe
• different surfaces (add sandpaper, wire netting, lino or carpet to the board to
change the ground surface)
• different lengths of board (a longer board will give a greater slope)
• measure the angle using trigonometry
• compare wet and dry surfaces

4. Experiment 3
Scenario: The suspect was seen at the other end of the school 5 minutes after the
crime was committed. How long could he have taken to get there.
Aim: to measure the speed of the suspect
Method:
1. work out the different routes from the crime scene to the point of sighting of
the suspect.
2. measure the distance each route would take
3. time how long it takes you to run each route and work out the speed you went
4. repeat each route three times and record your time in the table
Results:
Route number Distance of
route (m)
Time to run the
route (s)
Speed (m.s-1
) =
distance ÷ time
Average speed
1
2
Draw a bar graph of averages for each route
Conclusion: The suspect could (not) have committed the crime because…………
Possible further experiments
• change the sightings between different suspects (different suspects sighted at
different places around the school – eliminate those who couldn’t possibly
have done it)
• run, walk, use skateboards and bikes to get between sites