How to Calculate Pressure of Gas (Ideal Gas Law)

Ideal Gas Law Formula:

\[ P = \frac{n \times R \times T}{V} \]

Amount of Substance (n):

mol

Temperature (T):

Volume (V):

m³

Gas Constant (R):

J/mol·K

Pressure (P):

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1. What is the Ideal Gas Law?

Definition: The ideal gas law relates the pressure, volume, temperature, and amount of an ideal gas through the equation PV = nRT.

Purpose: It helps scientists and engineers calculate gas properties under various conditions, assuming ideal behavior.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ P = \frac{n \times R \times T}{V} \]

Where:

\( P \) — Pressure (Pascals)
\( n \) — Amount of substance (moles)
\( R \) — Universal gas constant (8.314 J/mol·K)
\( T \) — Temperature (Kelvin)
\( V \) — Volume (cubic meters)

Explanation: The product of moles, gas constant, and temperature is divided by volume to calculate pressure.

3. Importance of Ideal Gas Law

Details: This fundamental equation is used in chemistry, physics, and engineering to predict gas behavior under different conditions.

4. Using the Calculator

Tips: Enter the amount of gas in moles, temperature in Kelvin, volume in cubic meters, and gas constant (default 8.314 J/mol·K). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is an ideal gas?
A: An ideal gas is a theoretical gas whose molecules occupy negligible space and have no intermolecular forces.

Q2: When does the ideal gas law not apply?
A: At high pressures or low temperatures where real gases deviate from ideal behavior.

Q3: How do I convert Celsius to Kelvin?
A: Add 273.15 to the Celsius temperature (K = °C + 273.15).

Q4: Can I use different units?
A: Yes, but you'll need to adjust the gas constant value accordingly (e.g., 0.0821 L·atm/mol·K).

Q5: What's the significance of R?
A: The gas constant relates energy scale to temperature scale and serves as a proportionality constant in the equation.