Chem Lesson 4.3 Balancing Equations GC Edition

Chemical Equation

A representation of a chemical change, showing the reactants and products.

Reactants

The substances that undergo a chemical reaction, found on the left side of a chemical equation.

Products

The new substances formed as a result of a chemical reaction, found on the right side of a chemical equation.

Arrow (→)

Indicates the direction of a chemical reaction, meaning 'yields' or 'produces'.

Reversible Reaction

A reaction where the products can react to form the original reactants, indicated by a double arrow (⇌).

Subscript

Numbers written below and to the right of an element symbol, indicating the number of atoms of that element in a molecule.

Coefficient

A number placed in front of a molecule in a chemical equation to indicate the number of molecules present.

Aqueous (AQ)

A state of a substance that is dissolved in water.

Catalyst

A substance that speeds up a chemical reaction without being consumed or changed by the reaction.

Law of Conservation of Mass

States that matter cannot be created or destroyed in a chemical reaction; the number and types of atoms must remain constant.

Balanced Equation

An equation where the number of atoms of each element is the same on both sides of the equation.

Combustion Reaction

A type of chemical reaction that involves the reaction of a substance with oxygen to produce energy, typically as heat and light.

Polyatomic Ion

An ion that consists of two or more atoms bonded together that carries a charge.

Least Common Multiple (LCM)

The smallest multiple that is exactly divisible by each member of a set of numbers; useful for balancing equations.

Delta (Δ)

A symbol used to denote a change in energy or temperature during a reaction.

Heat Energy in Reactions

The energy change associated with a chemical reaction, indicated in joules or by the Greek letter delta.