International Baccalaureate IB Chemistry
1.4.1 Definition of the mole and Avogadro constant
Convert the amount of substance, $n$, to the number of specified elementary entities.
An elementary entity may be an atom, a molecule, an ion, an electron, any other particle or a specified group of particles.
The Avogadro constant $N_A$ is given in the data booklet. It has the units $\mathrm{mol^{-1}}$.
1.4.2 Relative atomic and formula masses
Determine relative formula masses $M_r$ from relative atomic masses $A_r$. No units. The values of relative atomic masses given to two decimal places in the data booklet should be used in calculations.
1.4.3 Molar mass (g mol⁻¹)
Solve problems involving the relationships between the number of particles, the amount of substance in moles and the mass in grams.
1.4.4 Empirical and molecular formulas
Interconvert the percentage composition by mass and the empirical formula. Determine the molecular formula of a compound from its empirical formula and molar mass.
1.4.5 Molar concentration (c)
Solve problems involving the molar concentration, amount of solute and volume of solution.
The use of square brackets to represent molar concentration is required. Units of concentration should include $g\,\text{dm}^{-3}$ and $mol\,\text{dm}^{-3}$ and conversion between these. The relationship $n = c V$ is given in the data booklet.
1.4.6 Avogadro’s law for gases
Solve problems involving the mole ratio of reactants and/or products and the volume of gases.