GCSE Chemistry AQA Topic – Atomic structure and the periodic table

Flashcards covering atoms, elements, the periodic table, and atomic structure.

Atom

The smallest part of an element that cannot be chemically broken down.

Element

Substance made of only one type of atom, each with its own symbol.

Compound

Contains more than one type of atom, formed from elements by chemical reactions.

Chemical Equation

Shows the reactants and products in a chemical reaction, ensuring no atoms are lost or made.

Reactants

The substances that we start with in a chemical reaction.

Products

The substances that we end with in a chemical reaction.

State Symbols

Symbols used in chemical equations to indicate whether reactants and products are solid (s), liquid (l), gas (g), or aqueous (aq).

Mixture

Consists of two or more elements or compounds not chemically combined; chemical properties are unchanged.

Filtration

Technique to separate insoluble substances from soluble ones using a solvent.

Solvent

The liquid in which a solute dissolves.

Solute

The substance that dissolves in a liquid to form a solution.

Solution

The mixture formed when a solute has dissolved in a solvent.

Crystallization

Technique to separate a soluble substance from a solvent by evaporation.

Simple Distillation

Technique to separate a liquid from a mixture by evaporation followed by condensation.

Fractional Distillation

Technique that separates a mixture into different parts (fractions) based on boiling points.

Chromatography

Technique to separate small amounts of dissolved substances by running a solvent along absorbent paper.

Dalton's Atomic Model

Early 1800s model proposing atoms as tiny, indivisible spheres.

Thomson's Plum Pudding Model

Model suggesting atoms are spheres of positive charge with negative electrons spread throughout.

Rutherford's Nuclear Model

Model based on scattering experiments, proposing atoms with a nucleus and orbiting electrons.

Bohr's Atomic Model

Model adapting Rutherford's, suggesting electrons orbit at specific distances in fixed energy levels.

Proton

Positively charged particle found in the nucleus of an atom.

Neutron

Neutral particle with a mass similar to a proton, found in the nucleus of an atom.

Isotope

Atoms of the same element with different numbers of neutrons.

Relative Atomic Mass

Average mass of an element, taking into account the abundance of its isotopes.

Electronic Structure

The arrangement of electrons in an atom's energy levels or shells.

Periodic Table

Arrangement of elements by increasing atomic number, with similar properties in columns (groups).

Groups

Vertical columns in the periodic table, containing elements with similar properties.

Periods

Horizontal rows in the periodic table.

Metals

Elements that tend to form positive ions; found towards the left and bottom of the periodic table.

Non-metals

Elements that do not form positive ions; found towards the right and top of the periodic table.

Noble Gases

Elements in Group 0; unreactive due to stable electron arrangements.

Alkali Metals

Elements in Group 1; very reactive metals with low densities.

Halogens

Elements in Group 7; toxic non-metals with colored vapors.

Diatomic Molecule

Molecules made up of pairs of atoms (e.g., F2, Cl2, Br2).

Transition Metals

Located between Group 2 and Group 3; high melting/boiling points, high densities, strong, and good conductors.

Catalyst

Substance that speeds up a chemical reaction without being used up.