The universal gas constant (R) is a constant that appears in the ideal gas law PV=nRTPV = nRT. Its value depends on the units used for pressure, volume, and temperature. Common values are:
- R = 8.314 J/(mol·K)
- Used when pressure is in Pascals (Pa) and volume is in cubic meters (m³).
- R = 0.0821 L·atm/(mol·K)
- Used when pressure is in atmospheres (atm) and volume is in liters (L).
- R = 62.36 L·Torr/(mol·K)
- Used when pressure is in Torr (or mmHg) and volume is in liters.
Key points:
- RR is a universal constant, meaning it is the same for all ideal gases.
- It links energy, pressure, volume, temperature, and amount of substance in gas calculations.