Molar volume of `CO_(2)` is maximum at

Options

A. `NTP`
B. `0^(@) C` and `2.0 atm`
C. `127^(@)C` and `1 atm`
D. `273^(@) C` and `2.0 atm`

Answer

C

Explanation

According to the ideal gas equation ,
`pV = nRT`
For `n = 1 , V = (RT)/(p)`
For maximum volume , we need maximum value of `(T//p)`.
At `NTP`,
`(T)/(p) = (273 K)/(1 "atm") = 273 K "atm"^(-1)`
At `0^(@)C` and `2 atm` ,
`(T)/(p) = (273 K)/(2 "atm") = 136.5 K "atm"^(-1)`
At `127^(@) C` and `1 "atm"` ,
`(T)/(p) = (400 K)/(1 "atm") = 400 K "atm"^(-1)`
At `273^(@) C` and `2.0 atm`,
`(T)/(p) = (546 K)/(2 "atm") = 273 K atm^(-1)`
Thus , the molar volume of `CO_(2)` is the maximum at `127^(@)C` and `1 atm`.