Formulae, Equations and Amount of Substance

Formulae, Equations and Moles

know the terms 'atom', 'element', 'ion', 'molecule', 'compound', 'empirical formula' and 'molecular formula' · know that the mole (mol) is the unit for the amount of a substance and be able to perform calculations using the Avogadro constant L (6.02 x 10^23 mol^-1) · write balanced full and ionic equations, including state symbols, for chemical reactions · understand the terms: (i) 'relative atomic mass' based on the 12C scale; (ii) 'relative molecular mass' and 'relative formula mass', including calculating these values from relative atomic masses (the term 'relative formula mass' should be used for compounds with giant structures); (iii) 'molar mass' as the mass per mole of a substance in g mol^-1; (iv) parts per million (ppm), including gases in the atmosphere · calculate the concentration of a solution in mol dm^-3 and g dm^-3 (titration calculations are not required at this stage)

Calculations from Equations

be able to use experimental data to calculate empirical and molecular formulae · be able to use chemical equations to calculate reacting masses and vice versa, using the concepts of amount of substance and molar mass · be able to use chemical equations to calculate volumes of gases and vice versa, using: (i) the concepts of amount of substance; (ii) the molar volume of gases; (iii) the expression pV = nRT for gases and volatile liquids · be able to calculate percentage yields and percentage atom economies (by mass) in laboratory and industrial processes, using chemical equations and experimental results (atom economy = molar mass of the desired product / sum of the molar masses of all products x 100%) · be able to determine a formula or confirm an equation by experiment, including evaluation of the data · CORE PRACTICAL 1: Measurement of the molar volume of a gas

Ionic Equations and Test-Tube ObservationsSign up

be able to relate ionic and full equations, with state symbols, to observations from simple test-tube experiments, to include: (i) displacement reactions; (ii) typical reactions of acids; (iii) precipitation reactions