3.3 Moles and volumes

• Concentration is the amount of moles of a substance in a given volume of solution
• Number of moles = concentration x volume
• Multiplying the concentration by the molecular mass will give the concentration in grams per dm3
• Molar gas volume increases as temperature increases
• Molar gas volume decreases as pressure increases
• At room temperature and pressure, 1 mole of gas occupies a volume of 24dm3
• Volume = moles x 24
• Ideal gas equation -> pV = nRT

  • p = pressure in Pascals
  • V = volume in m3
  • n = number of moles
  • R = gas constant
  • T = temperature in K