the mole and ideal gasses

• volume of gas: number of mole * 22.7
• pressure * volume = moles * 8.31 * temperature
• 0°C = 273 K
• molecular mass (Mr): number of atoms * atomic mass
• number of moles (n): mass (M) / molar mas (m)
• number of particles = number of moles * 6.02 x 10^23
• percentage composition: molar mass / mass of substance
• to find empirical formula:

  1. mass --> number of moles
  2. numeber of moles --> ratio
  3. ratio --> empirical formula
• concentration

  1. % by mass = mass (solute) / mass (solvent) * 100
  2. mass concentration = mass (solute) / volume (solvent)
  3. molarity = number of moles / volume (solution)
• C1 * V1 = C2 * V2
• 1. find concentration of old solution
  2. concentration new solution
  3. number of moles in sample (volume * concentration old)
  4. calculate concentration (n / volume)
• n1 / n2 = v1 / v2
• p1 * v1 / T1 = p2 * v2 / T2