Constant temperature compression of an ideal gas?

Question

An ideal gas is in contact with a heat reservoir so that it remains at a constant temperature of 300 K. The gas is compressed from a volume of 33 L to a volume of 18 L. During the process the mechanical device pushing the piston to compress the gas is found to expend 7 kJ of energy. What is the magnitude of the heat flow between the heat reservoir and the gas in kJ?

Answer 1

It is given "During the process the mechanical device pushing the piston to compress the gas is found to expend 7 kJ of energy". We wonder how much of this energy is doing the work on the gas and how much of this energy wasted in the low efficiency of the mechanics.
However, if 100% of the energy is used to compress the gas, the gas must flow 7kJ of heat to the reservoir, since the internal energy of the gas is not changed at all at a constant temperature.

Answer 2

The artwork performed on a gas with tension P with the aid of a metamorphosis in volume dV is -PdV. That artwork is going into starting to be the kinetic power of the gas molecules, meaning starting to be the temperature. it somewhat is the fluid description. From a molecular area of view, an elastic collision off an inwardly moving wall will consequences in impact in an advance interior the molecule's speed, only as a baseball will advance that's speed whilst it collides with a shifting bat.