Two moles of ideal helium gas are in rubber balloon at 30° C. The balloon is fully expandable and can be assumed to require no energy in its expansion. The temperature of the gas in the balloon is slowly changed to 35°C. The amount of heat required in raising the temperature is nearly, (Take R = 8.31 J/mol-K).
(A) 62 J
(B) 104 J
(C) 124 J
(D) 208 J
My answer is 208 J.
Is this answer correct?