calculations

A set of flashcards defining key chemistry concepts related to calculations and chemical formulas.

Relative Formula Mass (Mr)

The average mass of a compound or molecule compared to 1/12th of an atom of carbon-12, found by adding together the relative atomic masses of its constituent atoms.

Mole

An amount of substance that contains 6 x 10^23 particles.

Valency

The number of electrons needed to be gained or lost to achieve a full outer shell.

Aqueous

Dissolved in water.

Empirical Formula

The smallest whole number ratio of atoms of each element in a compound.

Molecular Formula

The actual number of atoms of each element in one molecule.

Water of Crystallisation

Water molecules trapped in a solid crystal when it forms, e.g., CuSO4.5H2O.

Yield

Amount of product made.