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?
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 ...
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