Advertisement Remove all ads

An Amount Q of Heat is Added to a Monatomic Ideal Gas in a Process in Which the Gas Performs a Work Q/2 on Its Surrounding. - Physics

Answer in Brief

An amount Q of heat is added to a monatomic ideal gas in a process in which the gas performs a work Q/2 on its surrounding. Find the molar heat capacity for the process

Advertisement Remove all ads


Amount of heat given to the gas = Q
So, ∆Q = Q

Work done by the gas, Δ W = `Q/2`

From the first law of thermodynamics,

ΔQ = ΔW +Δ U

`=> triangle "U" = "Q" - "Q"/2 = "Q"/2`

For a monoatomic gas,

`triangle "U"= 3/2 "n""R""d""T"`

`=> "Q"/2 = "n""d""T" xx3/2 "R"`

⇒ Q = 3nRdT

Again, for expansion at constant pressure,
Q = nCpdT, 
where Cp is the molar heat capacity at constant pressure.
So, 3RndT = nCpdT
⇒ Cp = 3R

Concept: Kinetic Theory of Gases and Radiation - Introduction of Kinetic Theory of an Ideal Gas
  Is there an error in this question or solution?
Advertisement Remove all ads


HC Verma Class 11, Class 12 Concepts of Physics Vol. 2
Chapter 5 Specific Heat Capacities of Gases
Q 8 | Page 78
Advertisement Remove all ads
Advertisement Remove all ads

View all notifications

      Forgot password?
View in app×