ideal gas equations and reacting gases

• what are the ideal gas equation symbols?

  P - pressure (Pa)

  V - volume (m3)

  n - moles

  R - gas constant (always 8.31JK-1mol-1)

  T - temperature (K)
• what is the conversion from °C to K?

  add 273
• what are the standard conditions for gas equations?

  298K

  100 000Pa
• what is the ideal gas calculation?

  PV = nRT
• example: a 2.16g sample of Fe(NO3)3 was completely converted.

  4Fe(NO3)3 --> 2FeO3 +12NO2 + 3O2

  calculate volume of NO2 at 293C, 100KPa produced

  moles of Fe(NO3)3 - 2.16 / 241.8 = 0.00893 moles

  moles of NO2 - 0.00893 x 3 = 0.02679 moles

  100000 x V = 0,02679 x 8.31 x (273+293)

  V = 0.00126m3
• example: 4dm3 of H2S is burned in 10dm3 of O2, what is the final volume of the mixture?

  2H2S + 3O2 --> 2H2O + 2SO2

  4dm3 6dm3 (used)

  H2O - 4dm3 (molar ratio)

  SO2 - 4dm3 (ratio)

  10-6 = 4dm3 (O2 left in mixture unreacted)

  4+4+4 =12dm3

  final volume = 12dm3