What is the Ideal Gas Law?

The Ideal Gas Law is a fundamental equation in chemistry and physics that approximates the behavior of most gases under various conditions. It combines several empirical gas laws (Boyle's Law, Charles's Law, and Avogadro's Law) into a single, comprehensive relationship between pressure, volume, temperature, and the amount of a gas.

Formula for the Ideal Gas Law

The relationship between these variables is expressed by the formula:

$$PV=nRT$$

Where:

  • Pis the absolute pressure of the gas.
  • Vis the volume of the gas.
  • nis the amount of substance of the gas (measured in moles).
  • Ris the ideal, or universal, gas constant.
  • Tis the absolute temperature of the gas (measured in Kelvin).

How to Use the Calculator

  1. Identify knowns:Determine which three of the four main variables (P, V, n, T) you know.
  2. Enter values:Input the three known values into their respective fields. The calculator will solve for the fourth.
  3. Select units:Choose the correct unit for each value you entered. The calculator handles all conversions automatically.
  4. Choose Gas Constant (R):Select the value of R that matches the units you are most comfortable with. The calculator will convert this internally as needed.
  5. View Instant Result:The value for the one field you left blank will be calculated instantly and highlighted in green.
  6. View Solution:A detailed, step-by-step solution will appear below the calculator.
  7. Clear:Click the "Clear" button to reset all fields for a new calculation.

Rearranged Formulas

To solve for a specific variable, the formula can be rearranged:

  • To find Pressure (P): $$P=\frac{nRT}{V}$$
  • To find Volume (V): $$V=\frac{nRT}{P}$$
  • To find Moles (n): $$n=\frac{PV}{RT}$$
  • To find Temperature (T): $$T=\frac{PV}{nR}$$
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Mr. Singh

Mr. Singh is a passionate educator and skilled writer who brings science to life. With a Master's in Physics and years of teaching, he combines 5+ years of coding and content creation expertise to make complex ideas engaging for everyone.