Quantitative Chemistry

1 Conservation of Mass and Balanced Equations Explain the law of conservation of mass and balance symbol equations. Spec 5.3.1.1 2 Relative Formula Mass Calculate relative formula mass (Mr) from relative atomic masses and use it in calculations. Spec 5.3.1.2 3 Mass Changes in Reactions Explain why the measured mass sometimes appears to change in a reaction and predict mass changes. Spec 5.3.1.3 4 Chemical Measurements Describe the importance of precise measurements in chemistry and sources of uncertainty. Spec 5.3.1.4 5 Percentage Yield Calculate percentage yield and explain why the actual yield is often less than the theoretical yield. Spec 4.3.3.1 6 Atom Economy Calculate atom economy and explain its importance for sustainable and efficient chemistry. Spec 4.3.3.2 7 Concentration of Solutions Define concentration and calculate it from mass and volume. Spec 5.3.2.5 8 Moles Define the mole, use the Avogadro constant and calculate moles from mass and Mr. Spec 5.3.2.1 9 Amounts of Substances in Equations Use balanced equations and moles to calculate masses of reactants and products. Spec 5.3.2.2 10 Using Moles — Calculations and Limiting Reactants Use moles to balance equations, calculate concentration in mol/dm³ and identify limiting reactants. Spec 5.3.2.3–5.3.2.4