An engineering team is testing different chemical formulations for an emergency cryo-therapy cold pack.
Their initial test results are recorded in the table below.
| Formulation | Initial temperature in °C | Temperature after 5 minutes in °C | Temperature change in °C |
|---|---|---|---|
| Alpha | 22.3 | 41.5 | +19.2 |
| Beta | 22.3 | 14.8 | -7.5 |
| Gamma | 22.3 | 6.8 |
Calculate the temperature change for formulation Gamma.
Include a sign (+++ or −-−) in your answer to show if the temperature change is an increase or a decrease.
94 exam-style questions on Edexcel GCSE Chemistry 8.2 Heat energy changes in chemical reactions, covering 8.2.1 Exothermic and endothermic changes, 8.2.2 Bond breaking, bond making and overall energy change, 8.2.3 Calculating energy change from bond energies, and 8.2.4 Activation energy and reaction profiles. Each one has a worked solution and a mark scheme showing where the marks go.