AQA GCSE Chemistry - Calculations involving masses PowerPoint

CALCULATIONS

, AIMS

Using relative atomic mass/moles you can calculate:
 Number of moles in a given mass of that substance and vice versa.
 Masses of products/reactants from balanced symbol equations or balance equations from give
 Percentage by mass from the relative formula mass and the relative atomic masses.
 Explain how the concentration of a solution in mol/dm3 is related to the mass of the solute and
volume of the solution.


Using masses from reactions:
 Calculate the percentage yield of a product from the actual yield of a reaction.
 Calculate the theoretical mass of a product from a given mass of reactant and the balanced eq
the reaction.
 Calculate the atom economy of a reaction to form a desired product from the balanced equati

, AIMS


Using gases/moles/volumes:
 Understand Avogadro’s constant.
 Calculate the volume of a gas at room temperature and pressure from its mass and relative for
mass.
 Calculate volumes of gaseous reactants and products from a balanced equation and a given v
gaseous reactant or product.


Enthalpy changes:
 Calculation energy changes from given bond enthalpies.