C1/2 Periodic table and atomic structure Flashcards
Alkali metals
Group 1 elements
Atom
The smallest part of an element that can exist
Atomic nucleus
Positively charged objects composed of protons and neutrons at the centre of every atom with one or more electrons orbiting it
Atomic number
The number of protons in the nucleus
Chromatography
A separation technique used to separate a mixture of chemicals by distributing the components between two phases
Compound
A substance made up of two or more chemically combined elements
Crystallisation
A separation technique used to produce solid crystals from a solution by evaporation the solvent
Displacement
A chemical reaction in which a more reactive element displaces a less reactive element from its compound
Electron
Negatively charged subatomic particles which orbit the nucleus at various energy levels. Very small relative mass.
Electron shell
Different energy levels in atoms occupied by electrons
Element
A substance made up of only one type of atom
Filtration
A separation technique used to separate solids from liquids
Fraction distilation
A method of separating a mixture of substances according to their different boiling points
Group
The columns of the periodic table represent different groups of elements. Element with similar properties are in the same group.
Halogens
The elements in group 7 of the periodic table