3.2.1 - enthalpy changes

Question 1

What are two potential errors in a combustion reaction of an alcohol that could give an enthalpy change less exothermic than expected

Answer 1

• removing the burner from under the beaker after recording the temperature and letting it burn for five minutes before weighing it
• recording the final temperature five minutes after removing the burner

Question 2

What is a potential error in a combustion experiment that would make the enthalpy change look more exothermic than expected?

Answer 2

Spilling some water on the bench when pouring water from the measuring cylinder into the beaker.

(Bigger temperature change as less water to heat)