Molar Mass Of Gas Calculator Gallons

Gas MW with volume in gallons:

\[ MW = \frac{(m \times R \times T)}{(P \times V_{gal} \times 0.003785)} \]

Mass of gas (m):

grams

Temperature (T):

Kelvin

Pressure (P):

atm

Volume (V_gal):

gallons

Molar Mass (MW):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Molar Mass of Gas Equation?

The molar mass of a gas can be calculated using the ideal gas law when the volume is measured in gallons. This equation is particularly useful in chemistry and physics for determining the molecular weight of an unknown gas.

2. How Does the Calculator Work?

The calculator uses the following equation:

\[ MW = \frac{(m \times R \times T)}{(P \times V_{gal} \times 0.003785)} \]

Where:

\( MW \) — Molar mass (g/mol)
\( m \) — Mass of gas (grams)
\( R \) — Universal gas constant (0.08206 L·atm·K⁻¹·mol⁻¹)
\( T \) — Temperature (Kelvin)
\( P \) — Pressure (atm)
\( V_{gal} \) — Volume (gallons)
0.003785 — Conversion factor from gallons to liters

Explanation: The equation is derived from the ideal gas law (PV = nRT) where n (moles) is equal to mass divided by molar mass (m/MW).

3. Importance of Molar Mass Calculation

Details: Calculating molar mass is essential for identifying unknown gases, stoichiometric calculations, and understanding gas behavior under different conditions.

4. Using the Calculator

Tips: Enter mass in grams, temperature in Kelvin, pressure in atmospheres, and volume in gallons. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why use Kelvin for temperature?
A: The ideal gas law requires absolute temperature, which Kelvin provides (0 K = absolute zero).

Q2: What is the value of the gas constant R?
A: R = 0.08206 L·atm·K⁻¹·mol⁻¹ when pressure is in atm and volume is in liters.

Q3: Can I use other pressure units?
A: Yes, but you'll need to adjust the gas constant R accordingly (e.g., 62.36 for mmHg).

Q4: How accurate is this calculation?
A: It works well for ideal gases at moderate temperatures and pressures. For real gases, corrections may be needed.

Q5: What's the conversion from gallons to liters?
A: 1 gallon = 3.78541 liters, which is why we multiply by 0.003785 to convert gallons to cubic meters.