A student investigated the temperature changes that occur when three different salts, P, Q, and R, are dissolved in water.
Their results are shown in the table below.
| Salt | Starting temperature of water in °C | Final temperature of mixture in °C | Temperature change in °C |
|---|---|---|---|
| P | 18.5 | 14.2 | -4.3 |
| Q | 18.5 | 24.1 | +5.6 |
| R | 18.5 | 31.3 |
Explain which salt produces the largest exothermic temperature change.
You should calculate the temperature change for salt R in your answer.
Practise Edexcel GCSE Chemistry Heat energy changes in chemical reactions with exam-style questions for Foundation and Higher tier. 130 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
