Definitons Flashcards
What are alkali metals?
The elements in Group 1 of the periodic table.
what is an atom?
The smallest part of an element that can exist. All substances are made up of atoms.
what is an atomic nucleus?
Positively charged object composed of protons and neutrons at the centre of every atom with one or more electrons orbiting it
What is an atomic number?
The number of protons in the nucleus.
What is chromotography?
A separation technique used to separate a mixture of chemicals by distributing the components between two phases.
What is a compound?
A substance made up of two or more types of atoms chemically combined together.
What is crystallisation?
A separation technique used to produce solid crystals from a solution by evaporating the solvent.
what is displacement?
A chemical reaction in which a more reactive element displaces a less reactive element from its compound.
What is an electron?
Negatively charged subatomic particle which orbit the nucleus at various energy levels. Very small relative mass (negligible).
What are the electron shells?
Different energy levels in atoms occupied by electrons.
What is an element?
A substance made up of only one type of atom.
What is filtiration?
A separation technique used to separate solids from liquids
What is fractional distiliation?
A method of separating a mixture of substances according to their different boiling points.
What is a group in a periodic table?
The columns of the periodic table represent different groups of elements. Elements with similar properties are in the same group.
