Exams › JEE Main › Chemistry
When 1 mol of a gas is heated at constant volume, temperature is raised from 298 to 308 K. If heat supplied to the gas is 500 J, then which statement is correct?
- q = w = 500 J, ΔU = 0
- ΔU = 500 J, w = 0
- q = w = 500 J, ΔU = 500 J
- ΔU = 0, q = w = -500 J
Correct answer: ΔU = 0, q = w = -500 J
Solution
At constant volume, ΔU = 0. The heat supplied to the gas is negative, so q = -500 J, and w = -500 J.
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