Exams › JEE Main › Chemistry
For one mole of an ideal gas, which of these statements must be true? (a) U and H each depends only on temperature (b) Compressibility factor z is not equal to 1 (c) C_p,m - C_v,m = R (d) dU = C_v dT for any process
- (a), (c) and (d)
- (b), (c) and (d)
- (c) and (d)
- (a) and (c)
Correct answer: (a) and (c)
Solution
Option (a) is correct because for an ideal gas, internal energy (U) and enthalpy (H) are functions of temperature alone, not volume or pressure. Option (c) is also correct as it reflects the relationship between the molar heat capacities at constant pressure and volume, which is a fundamental property of ideal gases.
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