One mole of ideal monoatomic gas (γ = 5/3) is mixed with two mole of diatomic gas (γ = 7/5). What is γ for mixture?

Correct answer: C. 19/13

  • A. 3/2
  • B. 23/15
  • C. 19/13
  • D. 4/3

Explanation

To find the effective gamma (γ) for the mixture, use the formula for the mixture of gases: γmix = (n1γ1 + n2γ2) / (n1 + n2), where n1 and n2 are the moles of each gas, and γ1 and γ2 are their respective gamma values. For this problem, n1 = 1 mole (monoatomic), γ1 = 5/3; n2 = 2 moles (diatomic), γ2 = 7/5. Therefore, γmix = (1*5/3 + 2*7/5) / (1+2) = (5/3 + 14/5) / 3 = 19/13. Hence, the correct answer is 19/13. The other options are incorrect because they either represent the gamma values of individual gases or miscalculate the mixture's gamma.

Written and checked by , contributorLast updated
Report an error

The more specific you are, the faster it gets fixed. A source beats an opinion.

Prefer email? [email protected]

About Molar Specific Heat of a Gas

Molar specific heat is the heat required to raise the temperature of one mole of a gas by one kelvin, expressed through Q = nCΔT. Questions compare the constant volume value Cv with the constant pressure value Cp, apply the ideal gas relation Cp − Cv = R, and identify how the thermodynamic process affects heat capacity.

Practise Thermodynamics

714 free Thermodynamics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Discussion

Stuck on an option, or know a faster way to get there? Ask or explain it here.

No comments yet. Be the first to explain this one.

Exams that ask Physics questions like this

Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

More Molar Specific Heat of a Gas questions