# Heat capacity and work done by various systems

Questions:

a. Calculate the heat capacity of a radiator coolant if a temperature rises from 5 to 107 °C requires 932 J of heat.

b. What is the change in internal energy for a system that does 7.02 kJ of work and absorbs 888 J of heat?

https://brainmass.com/physics/internal-energy/heat-capacity-work-done-various-systems-499228

#### Solution Preview

Both questions deal with chemical energetic. It is important to know the sign convention since this is a common

mistake that students make in problems dealing with chemical energetic.

a. The common formulas to deal with such problems are

q = ms?t = c?t, where q is the heat gained or lost, s is the specific heat capacity, c is the heat capacity and ? t the

change in temperature.

In this problem, the temperature of the radiator rises, meaning heat q is positive, thus

q = + 932 ...

#### Solution Summary

The heat capacity and the work done is calculated step-by-step for systems in different conditions. The sign convention is discussed and clarify in misconception