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Ideal Gas Law:  The basic relationship is PV=nRT where R =0.08206 L-atm mol^-1 K^-1

• Forms of the ideal gas law:

  • n = PV / RT

  • V = nRT / P

  • P = nRT / V

  • T= PV/nR

1. n = PV / RT; n =[(750mmHg/760mmHg atm^-1)(0.89 L)] / (0.08206 L-atm mole^-1K^-1)(294 K); n = 0.036

   • note that the units of the gas constant (0.08206 L-atm mole^-1K^-1 require that the units of other parameters are consistent, for example pressure is represented as atm (750mmHg/760mmHg atm^-1) and volume in L (890 mls becomes 0.89 L), as usual temperature is in degrees Kelvin

2. P=nRT/V; P= [(1.09g/2.02 g mol-1)(0.08206 L-atm mole^-1K^-1)(293K)] / 2 L; P = 6.48 atm. Also to convert from atm to mmHg, multiply by 760 mmHg/atm

3. V = nRT / P; V = [(3.00 moles)(0.08206 L-atm mole^-1K^-1) (297K)]/(762.4 mmHg/760 mmHg/atm); V=73 L

4. V = nRT / P; V = [(1.27 moles)(0.08206 L-atm mole^-1K^-1) (273K)]/1.00 atm = 28.45 L

5. n = PV / RT; n= [(100 atm)(50L)] / [(0.08206 L-atm mole^-1K^-1) (308K) = 197.8 moles