Topic 1 - Atomic Structure and the Periodic Table Flashcards
Alkali metals
The elements in Group 1 of the periodic table.
Atom
The smallest part of an element that can exist. All substances are made up of atoms.
Atomic nucleus
Positively charged object 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 types of atoms chemically combined together.
Crystallisation
A separation technique used to produce solid crystals from a solution by evaporating the solvent.
Displacement
A chemical reaction in which a more reactive element displaces a less reactive element from its compound.
Electron
Negatively charged subatomic particle which orbit the nucleus at various energy levels. Very small relative mass (negligible).
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.
Fractional distillation:
A method of separating a mixture of substances according to their different boiling points.
Group (periodic table)
The columns of the periodic table represent different groups of elements. Elements with similar properties are in the same group.
Halogens
The elements in Group 7 of the periodic table.
lon
An atom or molecule with an electric charge due to the loss or gain of electrons.
Isotope
Atoms of the same element with the same number of protons but a different number of neutrons.
Mass number:
The total number of protons and neutrons in the nucleus.
Metals
Elements that react to form positive ions. Found to the left and towards the bottom of the periodic table.
Mixture
A mixture consists of two or more elements or compounds not chemically combined together.
Neutron
Neutral subatomic particle present in the nucleus of the atom. Relative mass of 1.
Noble gases
The elements in Group 0 of the periodic table.
Non-metals
Elements that react to form negative ions. Found towards the right and top of the periodic table
Nuclear model
The nuclear atomic model stated that the mass was concentrated at the centre of the atom and that the nucleus was charged.
Periodic table
Table of elements arranged in order of atomic number and such that elements with similar properties are in the same column (group).
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.
Proton
Positively charged subatomic particle present in the nucleus of the atom. Relative mass of 1
Relative atomic mass
An average value that takes account of the abundance of the isotopes of the element.
Simple distillation
A procedure by which two liquids with different boiling points can be separated.
Transition metals
The collection of metallic elements in the middle of the periodic table.
How are the element listed and approximately how many are there?
They are listed in the periodic table; there are approximately 100.
Elements can be classified into two groups based on their properties; what are these groups?
Metals and non-metals
What are the methods through which mixtures can be separated (there are five)? Do these involve chemical reactions?
Filtration, crystallisation, simple distillation, fractional distillation and
chromatography; they do not involve chemical reactions