Quantitative chemistry

• Concentrations of solutions are measured in g/dm^3.
• The empirical formula of a compound is the simplest formula that shows the numerical relationships of the elements in the compound.
• The chemical formula of hydrogen peroxide is H2O2. What is the empirical formula of hydrogen peroxide?


  HO
• Stoichiometry is the ratio of moles of one substance to another in a reaction.
• moles = mass in grams ÷ relative atomic / formula mass
• A decimetre cubed is 1000 cubic centimetres.
• concentration (in moles per decimetre) = moles ÷ volume (in decimetre cubed)
• Percentage yield = (total mass of products ÷ total mass of reactants) × 100
• atom economy = (relative atomic mass of products ÷ total relative atomic mass of reactants) × 100
• 1 mole of any gas takes up a volume of 24 decimetres cubed.
• Moles = mass ÷ relative atomic mass
• The relative formula mass of a compound is the sum of relative atomic masses of atoms in the formula.
• The numbers of atoms, molecules or ions in a mole of any substance is the Avogadro constant.
• The value of the Avogadro constant is 6.02x10²³ per mole
• The volume of one mole of any gas at room temperature and pressure is 24 dm³
• Percentage yield = actual yield / theoretical yield x 100%
• Concordant results are within 0.1 cm³ of each other
• moles = concentration × volume
• Concentration = moles ÷ volume
• moles = mass ÷ molar mass
• Moles = "grams" ÷ "rams"