What are the units for the Ideal Gas Law (PV=nRT)?

In the ideal gas law equation, PV = nRT, it is crucial to ensure consistency in units to obtain accurate and meaningful results. Here's a breakdown of the units for each variable:

Conversions:
Moles to Grams:    • Convert from Moles to Grams, Liters, ...  
Celsius to Kelvin:    • How to Convert 37° Celsius to Kelvin  
mL to L:    • Convert 250mL to L  (250 milliliters ...  

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Pressure (P):

The SI unit for pressure is the pascal (Pa), but in many chemistry problems, pressure is often expressed in atmospheres (atm).
If pressure is given in a unit other than atmospheres, a conversion might be necessary. For example, if pressure is in millimeters of mercury (mmHg), the conversion factor is 1 atm = 760 mmHg.
Volume (V):

The SI unit for volume is the cubic meter (m³), but in chemistry, it is commonly expressed in liters (L).
If volume is given in milliliters (mL), a conversion to liters is required (1 L = 1000 mL).
Number of Moles (n):

Moles are a unit of measurement used to express the amount of a substance.
If the quantity is given in grams, convert it to moles using the molecular weight or molar mass of the substance.
Temperature (T):

Temperature should be in Kelvin (K) for the ideal gas law equation.
If given in Celsius (°C), convert to Kelvin using the formula K = °C + 273.15.
Ideal Gas Constant (R):

The ideal gas constant (R) depends on the units used for pressure.
If pressure is given in atmospheres, the commonly used value for R is 0.0821 L•atm/(mol•K).
If pressure is given in pascals (Pa), R is 8.314 J/(mol•K).


It's crucial to convert all units to the appropriate ones. For example, if you have pressure in mmHg, convert it to atmospheres, if volume is in milliliters, convert it to liters, and ensure moles and temperature are in the right units. Additionally, always check the given pressure unit to determine which value of R to use in the calculations.