DP Biology (last assessment 2024)
Question 20N.3.SL.TZ0.16d
Date | November 2020 | Marks available | [Maximum mark: 2] | Reference code | 20N.3.SL.TZ0.16d |
Level | SL | Paper | 3 | Time zone | TZ0 |
Command term | Explain | Question number | d | Adapted from | N/A |
d.
[Maximum mark: 2]
20N.3.SL.TZ0.16d
(d)
The apparatus used to measure energy content of food contains some water. Explain how this water is used when measuring the energy content of a food.
[2]
Markscheme
a. the volume/mass of water is measured;
b. the energy from the burning food raises the temperature/heats the water;
c. knowing the specific heat of water allows energy of the food to be calculated
OR
4.2J of heat energy causes a 1°C rise in 1g of water;
Examiners report
Stronger candidates could explain how water is used in a calorimeter. Many candidates suggested burning the food in the water and others answered all they knew about calorimeters without answering the question directly.
