Q. Two moles of ideal helium gas are in a rubber balloon at $30^{\circ} C$. 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 $35^{\circ} C$. The amount of heat required in raising the temperature is nearly $($ take $R =8.31 J / mol . K )$
AIEEEAIEEE 2012
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