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2 Atoms, Molecules and Stoichiometry

Cambridge AS Level Chemistry (9701) · 4 topics

Relative masses

The Unified Atomic Mass Unit Unified Atomic Mass Unit (u or amu) One twelfth of the mass of a carbon-12 atom. It is the standard unit used to express the masses…
The mole

The Mole and the Avogadro Constant The Mole (mol) The SI unit of amount of substance. One mole of any substance contains exactly 6.02 × 10²³ elementary entities…
Chemical formulae and equations

Types of Formula Empirical Formula The simplest whole-number ratio of atoms of each element in a compound. Molecular Formula The actual number of atoms of each…
Reacting masses and volumes

Reacting Masses Stoichiometric coefficients in a balanced equation give the molar ratios in which substances react and are produced. These ratios are used to…