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Question 1

Common errors in investigation [4]

Answer 1

1) Inaccurate measurement of dependent or independent variable
2) Failing to keep controlled variables constant
3) Failing to do repeats
4) Contaminated equipment

Question 2

Designing investigation [5]

Answer 2

1) State IV
2) State DV
3) State controlled variable
4) Give detailed method like recipe
5) Repeats

Question 3

Drawing tables [3]

Answer 3

1) Use ruler
2) All variables with unit
3) each cell with unit

Question 4

Histogram vs bar chart

Answer 4

1) Histogram for 2 continuous variables
2) Bar graph for 1 continuous variable

Question 5

Magnification formula

Answer 5

Image size= Actual x magnification

Question 6

Food test for glucose [3]

Answer 6

1) Add Benedict’s solution
2) Heat in water bath
3) A positive test will show a colour change from blue to orange or brick red

Question 7

Food test for starch [2]

Answer 7

1) Add iodine
2) A positive test will show a colour change from orange-brown to blue-black

Question 8

Food test for protein [2]

Answer 8

1) Add biuret solution
2) A positive test will show a colour change from blue to violet / purple

Question 9

Food test for lipids [2]

Answer 9

1) mixed with ethanol and shaken
2) A positive test will show a cloudy emulsion forming