A Level Chemistry OCR Practice Exam

What is the specific heat capacity?

1. The heat needed for a phase change

2. The energy required to raise the temperature of 1 g of a substance by 1 °C

3. The energy released during combustion

4. The heat required to convert a liquid into vapor

The correct answer is: The energy required to raise the temperature of 1 g of a substance by 1 °C

The correct answer is the energy required to raise the temperature of 1 g of a substance by 1 °C. This definition of specific heat capacity is fundamental in understanding how different substances absorb and transfer heat. It provides a measure of how much energy is needed to change the temperature of a given mass of a substance, reflecting its thermal properties. Specific heat capacity is a crucial concept in various applications, such as calorimetry and thermal analysis, where knowing how much energy is needed to change the temperature of a material is important for calculations regarding heat transfer in chemical reactions or physical processes. The other options pertain to different thermal processes. The heat needed for a phase change refers to latent heat, which is concerned with energy changes without temperature variation. The energy released during combustion pertains to exothermic reactions and is not directly related to the specific heat capacity concept. Lastly, the heat required to convert a liquid into vapor also describes a phase change (specifically vaporization) and does not address the specific heat needed to increase temperature.