1. What is Specific Gas Constant?

The specific gas constant (R_specific) is the universal gas constant (R) divided by the molar mass (MW) of the gas. It is a property of a particular gas and is used in various thermodynamic calculations.

2. How Does the Calculator Work?

The calculator uses the specific gas constant equation:

Where:

• \( R \) — Universal gas constant (8.314 J/mol K)
• \( MW \) — Molecular weight of the gas (g/mol)
• \( R_{specific} \) — Specific gas constant (J/kg K)

Explanation: The equation shows that the specific gas constant is inversely proportional to the molecular weight of the gas.

3. Importance of Specific Gas Constant

Details: The specific gas constant is crucial in thermodynamics for calculating properties of gases, including in the ideal gas law when working with mass-specific quantities.

4. Using the Calculator

Tips: Enter the molecular weight of the gas in g/mol. The value must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between R and R_specific?
A: R is the universal gas constant (same for all gases), while R_specific is unique to each gas and depends on its molecular weight.

Q2: What are typical values of R_specific?
A: For air (MW ≈ 28.97 g/mol), R_specific ≈ 287 J/kg K. For hydrogen (MW ≈ 2.016 g/mol), R_specific ≈ 4124 J/kg K.

Q3: Why is the unit J/kg K?
A: Because we're dividing J/mol K by g/mol and converting to kg, resulting in J/kg K.

Q4: Can this be used for gas mixtures?
A: Yes, but you need to use the effective molecular weight of the mixture.

Q5: How does temperature affect R_specific?
A: R_specific is constant for a given gas, independent of temperature or pressure.