Level 1 Chemistry: The Chemical World Flashcards

A set of vocabulary flashcards covering basic chemistry concepts including atomic structure, chemical reactions (combustion, neutralisation, combination, decomposition, precipitation), and properties of acids and bases.

Atoms

The building blocks of all matter, made up of PROTONS, NEUTRONS, and ELECTRONS.

Nucleus

The centre of the atom containing protons and neutrons.

Protons

Subatomic particles with a mass of $1\,amu$ and a charge of $+1$.

Neutrons

Subatomic particles with a mass of $1\,amu$ and a charge of $0$.

Electrons

Subatomic particles with a charge of $-1$ and a negligible mass approximately $2000$ times smaller than protons or neutrons.

Elements

Specific types of atoms identified by a unique atomic number.

Atomic number

The unique number determined by the number of protons in an element's nucleus.

Mass number

The total number of protons AND neutrons an element has in its nucleus.

Aufbau principle

The rule stating that electrons will fill up shells or energy levels from the lowest level up.

Electron Arrangements

The distribution of electrons in shells, following the rule $2, 8, 8, 2$ for the first $20$ elements.

Ion

A charged atom that has lost or gained electrons to achieve a complete outer shell.

Polyatomic Ions

Ions that are made up of multiple different kinds of atoms, such as $OH^-$ (hydroxide) or $SO_4^{2-}$ (sulfate).

Ionic Compounds

Compounds formed when positive and negative ions combine to reach a neutral state where the total charge equals $0$.

Law of Conservation of Mass

A law stating that matter cannot be created or destroyed, requiring the same number and types of atoms on each side of a chemical equation.

Combustion

A chemical reaction between a fuel and oxygen that gives off heat and light energy.

Complete Combustion

A reaction occurring with a plentiful supply of oxygen, producing carbon dioxide ($CO_2$) and water ($H_2O$).

Incomplete Combustion

A reaction occurring without a plentiful supply of oxygen, producing carbon monoxide ($CO$) and Carbon ($C$, also known as soot).

Limewater

Calcium hydroxide solution used as a test for Carbon Dioxide, which forms a milky white precipitate and appears cloudy when it reacts.

Acids

Substances that contain $H^+$ (Hydrogen) ions and dissociate into ions when added to water.

Bases

Substances considered opposite to acids, including metal hydroxides, metal oxides, and metal carbonates.

Alkalis

Bases that can dissolve in water and dissociate to form $OH^-$ (hydroxide) ions.

Dissociation

The process where an acid or base molecule breaks apart into its ions when added to water.

Strong Acids

Acids that completely dissociate when added to water, such as Hydrochloric acid ($HCl$), Sulfuric acid ($H_2SO_4$), and Nitric acid ($HNO_3$).

Weak Acids

Acids that only partially dissociate when added to water, such as organic acids like ethanoic acid.

pH Scale

A tool from $0$ to $14$ used to describe how acidic or basic a molecule is based on the concentration of hydrogen or hydroxide ions.

Neutralisation

A chemical reaction between an acid and a base to form a salt and water.

Combination Reactions

Reactions involving two or more reactants combining to form one larger product ($A + B \rightarrow AB$).

Decomposition Reactions

Reactions where one reactant decomposes to form two or more products ($AB \rightarrow A + B$).

Thermal Decomposition

A type of decomposition reaction that occurs in the presence of heat.

Precipitation Reactions

A reaction occurring when two ionic solutions are mixed to form an insoluble product called a precipitate.

Solute

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

Solvent

The substance (often water) in which a solute dissolves.

Insoluble

A term describing a substance that does not dissolve in a solvent.

Spectator Ions

Ions present in a solution that are not involved in the formation of a precipitate.