GCSE AQA Foundation Combined Science Chemistry · Topic 3 of 11
Choose a subtopic. Topic 3: Quantitative chemistry covers Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, Use of amount of substance in relation to masses of pure substances, Yield and atom economy of chemical reactions (chemistry only), and Using concentrations of solutions in mol/dm 3 (chemistry only) (HT only) in GCSE AQA Foundation Combined Science Chemistry. 6 lessons in 5 subtopics.
Revise Topic 3: Quantitative chemistry for GCSE AQA Foundation Combined Science Chemistry. 6 lessons across 5 subtopics.
6
Lessons
5
Subtopics
Topic 3: Quantitative chemistry has 5 subtopics:
6 lessons, grouped by subtopic.
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Topic 3: Quantitative chemistry covers Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, Use of amount of substance in relation to masses of pure substances, Yield and atom economy of chemical reactions (chemistry only), and Using concentrations of solutions in mol/dm 3 (chemistry only) (HT only) in GCSE AQA Foundation Combined Science Chemistry. 6 lessons in 5 subtopics.
The law of conservation of mass states that no atoms are lost or made during a chemical reaction, so the mass of the products equals the mass of the reactants. The The Law of Conservation of Mass notes cover this in full.
Percentage uncertainty = uncertainty ÷ measured value × 100. The Understanding Uncertainty in Chemical Measurements notes cover this in full.
Relative formula mass (Mr) is calculated by adding up the relative atomic masses of all the atoms in a formula: multiply each element's relative atomic mass by its number of atoms, then add them together. The Calculating Relative Formula Mass notes cover this in full.
To balance a chemical equation, count the atoms of each element on both sides, then change the coefficients in front of the formulae until every element has the same number of atoms on each side. The Balancing Chemical Equations notes cover this in full.
Percentage by mass of an element = total relative atomic mass of that element in the formula ÷ Mr of the compound × 100. The Percentage by Mass in Compounds notes cover this in full.
The relative formula mass of calcium carbonate, CaCO₃, is 100. The Percentage by Mass in Compounds notes cover this in full.
The relative atomic mass of carbon is 12. The Calculating Relative Formula Mass notes cover this in full.
The relative formula mass (Mr) of water, H₂O, is 18. The Calculating Relative Formula Mass notes cover this in full.