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.
Define Ion
An atom or molecule with an electric charge due to the loss or gain of electrons.
Define Isotope
Atoms of the same element with the same number of protons but a different number of neutrons.
Define Mass Number
The total number of protons and neutrons in the nucleus.
Define Metals
Elements that react to form positive ions. Found to the left and towards the bottom of the periodic table.
Define Mixture
A mixture consists of two or more elements or compounds not chemically combined together.
Define Neutron
Neutral subatomic particle present in the nucleus of the atom. Relative mass of 1.
Define Noble Gases
The elements in Group 0 of the periodic table.
Define Non-Metals
Elements that react to form negative ions. Found towards the right and top of the periodic table.
Define Nuclear Model
The nuclear atomic model stated that the mass was concentrated at the centre of the atom and that the nucleus was charged.
Define Periodic Table
Table of elements arranged in order of atomic number and such that elements with similar properties are in the same column (group).
Define Plum Pudding Model
Atomic model devised after the discovery of the electron. The model suggests the atom is a ball of positive charge with negative electrons scattered through it.
Define Proton
Positively charged subatomic particle present in the nucleus of the atom. Relative mass of 1.
Define Relative Atomic Mass
An average value that takes account of the abundance of the isotopes of the element.
Define Simple Distillation
A procedure by which two liquids with different boiling points can be separated.
Define Transition Metals
The collection of metallic elements in the middle of the periodic table.