# Mechanical Engineering - Thermodynamics - Discussion

Discussion Forum : Thermodynamics - Section 7 (Q.No. 11)
11.
The universal gas constant (or molar constant) of a gas is the product of
molecular mass of the gas and the gas constant
atomic mass of the gas and the gas constant
molecular mass of the gas and the specific heat at constant pressure
molecular mass of the gas and the specific heat at constant volume
Explanation:
No answer description is available. Let's discuss.
Discussion:
4 comments Page 1 of 1.

Chethankumar h e said:   6 years ago
The specific gas constant" of a gas or a mixture of gases. It is denoted as Rs and is defined as the universal gas constant divided by the molecular weight (M) of the specific gas or gas mixture.

The adjacent table lists some example values of Rs for a number of gases.
Rs=R/M.

For an ideal gas, the specific gas constant is related to the specific heats the gas:
Rs=cp/cv.

Akash said:   7 years ago
The Universal Gas Constant - Ru.
The Universal Gas Constant - Ru - appears in the ideal gas law and can be expressed as the product between the Individual Gas Constant - R - for the particular gas - and the Molecular Weight - Mgas - for the gas, and is the same for all ideal or perfect gases:

Ru = Mgas R --->(1)

where
Ru = universal gas constant
Mgas = molecular weight of the ideal gas or mixture of gases.

Babu said:   7 years ago
No @Samujawal.

Because mass of each gas is different so R=R (on top bar-)*M.