Investigating and interpreting

Question 1

What does repeatable mean?

Answer 1

Repeatable means that if the same person repeats the experiment using the same methods and equipment, they will get the same results.

Question 2

What does reproducible mean?

Answer 2

Reproducible means that if someone different does the experiment, the results they get will be the same.

Question 3

What are valid results?

Answer 3

Valid results answer the original question. To get valid results you need to control all the variables to make sure you’re only testing the thing you want to.

Question 4

How many variables should be changed?

Answer 4

One

Question 5

Which variable should be changed?

Answer 5

Independent variable

Question 6

Which variable should be controlled?

Answer 6

Control variable

Question 7

Which variable should be measured?

Answer 7

Dependent variable

Question 8

Why should you repeat the experiment at least three times?

Answer 8

Doing repeats and getting similar results each time shows you that your data is repeatable. This ensures that your results can be reproduced by someone else. Doing repeats also allows you to spot any anomalous results which don’t fit with the rest.

Question 9

What are negative controls?

Answer 9

Negative controls are used to check that the only independent variable is affecting the dependent variable. Negative controls are not expected to have any effect on the experiment.

Question 10

Which variable goes on the x-axis?

Answer 10

The independent variable

Question 11

Which variable goes on the y-axis?

Answer 11

The dependent variable

Question 12

How do you find the rate of reaction using a line graph?

Answer 12

By finding the gradient of the line

Question 13

How do you find the rate of the reaction using a curved graph?

Answer 13

By drawing a tangent