ISA/SCIENCE SKILLS

Question 1

A control is set up. What is its purpose?

Answer 1

1) To find the negative test
- which variable causes colour change

2) Ensure method is effective
- ie washing, dilution etc

Question 2

What is the advantage of showing something as a ratio?

Answer 2

1) Allows comparison to be made between two variables

2) Link to context
- ie start and end mass/conc/length were different

Question 3

Why take extra results?

Answer 3

Improves reliability BECAUSE….

1) Allows a mean to be calculated
2) Allows anomylous results to be calculated
3) Calculate SD/error bars
4) More representative/ larger sample size

Question 4

Why could extra readings improve a graph?

Answer 4

1) plot a more reliable curve/ line of best fit

2) intercept is more precise

Question 5

A student continues their graph beyond the set of results!

Answer 5

Is it extrapolate?

• you can’t predict outside your range as variance to the trend could occur
• did the graph level off?

Does it start at the origin?
- if 0 x gives 0y

Question 6

What measurements could a student make?

Answer 6

Look at the context
What are they trying to find?
What could make another student carrying out the same test get different results
ie) apparatus difference