A student investigated the ease with which various metal carbonates decompose on heating. She decide to heat equal masses of each carbonate and time how long it took for the carbon dioxide  given off to turn limewater in a test tube cloudy.

a. i. Name the independent variable in the investigation.

ii. Name the dependent variable.

iii. Name the control variable described at the start of this question.

b. The student decided to repeat the test on each of five metal carbonates provided three times.

i. Why is it a good idea to collect replicate data in investigations?

ii. Draw a table that the student could fill in as the investigation was carried out.

c. i. The test tube contained 10 cm³ of limewater. The student measured this volume in a 10 cm³ measuring cylinder with calibration marks every 0.1 cm³. What is the margin of error when reading this scale and what is the percentage error in measuring the volume of limewater for this investigation?

ii. Explain what is likely to be the greatest source of error in this investigation.

d. What type of graph should the student use to display the data from the investigation?

Transcribed Image Text:

metal carbonate heat - limewater