What will be the change in internal energy when $$12$$ $$kJ$$ of work is done on the system and $$2 \ kJ$$ of heat is given by the system?
Heat evolved $$= -2 kJ$$
Work done on the system $$= +12 kJ$$
$$\Delta U $$= q + w$$
$$= -2 + 12$$
$$= +10 kJ$$
Hence, option $$A$$ is correct.
An ideal gas does work on its surroundings when it expands by 2.5 L against external pressure 2 atm. This work done is used to heat up 1 mole of water at 293 K. What would be the final temperature of water in Kelvin if specific heat for water is 4.184 $$Jg^{-1} K^{-1}$$?
$$W$$ is positive when the work is done on the system.
According to IUPAC conventions work done on the surroundings is: