One mole of an ideal gas at 300K is taken through a reversible isothermal process.
(a) During the first attempt, the gas expands and does 500J of work.
(b) In a second attempt at the same temperature, only 350J of heat can be supplied from the reservoir; the desired isothermal condition is still to be maintained.
Answer the following:
(i) For part (a), state the value of ΔU and explain your reasoning.
(ii) For part (a), find the magnitude and algebraic sign of the heat exchanged Q.
(iii) For part (b), determine the magnitude and algebraic sign of the mechanical work that must be done on the gas so that its temperature remains unchanged.
(iv) Explain briefly how the signs chosen in parts (ii) and (iii) are consistent with the First Law.