Topic 1 Atomic structure and the Periodic Table Flashcards
Key Terms/Key Knowledge
Define Alkali Metals
The elements in Group 1 of the periodic table.
Define Atom
The smallest part of an element that can exist. All substances are made up of atoms.
Define Atomic Nucleus
Positively charged object composed of protons and neutrons at the centre of every atom with one or more electrons orbiting it.
Define Atomic Number
The number of protons in the nucleus.
Define Chromatography
A separation technique used to separate a mixture of chemicals by distributing the components between two phases.
Define Compound
A substance made up of two or more types of atoms chemically combined together.
Define Crystallisation
A separation technique used to produce solid crystals from a solution by evaporating the solvent.
Define Displacement
A chemical reaction in which a more reactive element displaces a less reactive element from its compound.
Define Electron
Negatively charged subatomic particle which orbit the nucleus at various energy levels. Very small relative mass (negligible).
Define Electron Shell
Different energy levels in atoms occupied by electrons.
Define Element
A substance made up of only one type of atom.
Define Filtration
A separation technique used to separate solids from liquids.
Define Fractional Distillation
A method of separating a mixture of substances according to their different boiling points.
Define Group (periodic table)
The columns of the periodic table represent different groups of elements. Elements with similar properties are in the same group.
Define Halogens
The elements in Group 7 of the periodic table.