Molar Heat Capacities: a Certain Amount of Ideal Monatomic Gas

Multiple Choice

Molar heat capacities: A certain amount of ideal monatomic gas is maintained at constant volume as it is cooled from 455K to 405 K. This feat is accomplished by removing 400 J of heat from the gas. How much work is done by the gas during this process? The ideal gas constant is R = 8.314 J/mol ∙ K.

A) 0.00 J
B) 200 J
C) 400 J
D) -400 J
E) -200 J