Question 1

What is the ideal gas law?

Accepted Answer

The ideal gas law PV = nRT relates pressure (P), volume (V), amount (n in moles), and temperature (T in Kelvin) of an ideal gas. R is the universal gas constant (0.08206 L·atm/(mol·K)).

Question 2

What is STP?

Accepted Answer

STP (Standard Temperature and Pressure) is 0°C (273.15 K) and 1 atm. At STP, one mole of any ideal gas occupies 22.414 liters (the molar volume).

Question 3

When does the ideal gas law fail?

Accepted Answer

The ideal gas law fails at high pressures, low temperatures, and for gases with strong intermolecular forces. Under these conditions, real gas equations like the van der Waals equation provide better results.

Question 4

Why must temperature be in Kelvin?

Accepted Answer

The ideal gas law requires absolute temperature because gas volume is proportional to absolute temperature. Using Celsius would give wrong results since 0°C is not truly zero temperature.

Ideal Gas Law Calculator (PV = nRT)

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