Answer:
DU = -80 Joules
Step-by-step explanation:
Given the following data;
Work done = 100 J
Quantity of heat = 20 J
To find change in internal energy of the gas;
Mathematically, the change in internal energy of a system is given by the formula;
DU = Q - W
Where;
DU is the change in internal energy.
Q is the quantity of energy.
W is the work done.
Substituting the values into the formula, we have;
DU = 20 - 100
DU = -80 Joules
Therefore, the final energy of the gas is lower than its initial energy.