Calculations Flashcards
Atomic number
the number of protons in an atom (which is equal to the number of electrons).
Neutron
a dense particle found in the nucleus of an atom. Has no charge.
Mass number
the number of protons and neutrons in the nucleus of an atom.
Isotope
atom that has the same number of protons but different number of neutrons.
Relative atomic mass
the average mass of the atoms of an element compared with carbon-12.
Relative formula mass
the total of all the relative atomic mass of the elements in a compound.
Mole
the amount of substance in the relative atomic or formula mass of a substance in grams.
Empircal formula
the simplest ratio of elements in a compound.
Molecular formula
the chemical formula that shows the actual numbers of atoms in a particular molecule.
Percentage yield
the actual mass of product collected in a reaction divided by the maximum mass that could have been formed in theory, multiplied by 100.
Reversible reactions
a reaction in which the products can re-form the reactants.
Chromatography
the process whereby small amounts of dissolved substances are separated by running a solvent along a material such as paper.
Gas chromatography
the process of separating the components in a mixture by passing the vapours through a column and detecting them as they leave the column at different times.
Retention time
the time it takes a component in a mixture to pass through the column during gas chromatography.
Mass spectrometer
a machine that can be used to analyse small amounts of a substance to identify it and to find its relative molecular mass.
