Chemistry Definitions and Intermolecular Forces

Vocabulary practice cards covering key definitions in Quantitative Chemistry, Bonding, Energy Changes, Acids and Bases, Electrochemistry, Organic Chemistry, and Intermolecular Forces.

Molar Mass

The mass in grams of one mole of that substance.

Molar Concentration

The amount of solute per unit volume of solution.

Electronegativity

A measure of the tendency of an atom to attract a bonding pair of electrons.

Heat of a Reaction ($\Delta H$)

The net change of chemical potential energy of the system.

Exothermic Reactions

Reactions which transform chemical potential energy into thermal energy.

Endothermic Reactions

Reactions which transform thermal energy into chemical potential energy.

Activation Energy

The minimum energy required to start a chemical reaction OR the energy required to form the activated complex.

Activated Complex

A high energy, unstable transition state between the reactants and the products.

Reaction Rate

The change in amount or concentration per unit time of either a reactant or product.

Catalyst

A substance that increases the rate of the reaction but remains unchanged at the end of the reaction.

Hydrocarbon

A compound containing only carbon and hydrogen atoms.

Saturated Compound

A compound in which all of the bonds between carbon atoms are single bonds.

Unsaturated Compound

A compound in which there is at least one double and/or triple bond between carbon atoms.

Functional Group

An atom or a group of atoms that form the centre of chemical activity in the molecule.

Homologous Series

A series of similar compounds which have the same functional group and have the same general formula, in which each member differs from the previous one by a single $\text{CH}_2$ unit.

Structural Isomers

Compounds having the same molecular formula but different structural formulae.