5.1 Energy in Chemical Reactions

Vocabulary flashcards covering key terms from the Energy in Chemical Reactions notes, including reactants/products, types of reactions, and common examples.

Reactants

Substances you start with in a chemical reaction.

Products

Substances formed at the end of a chemical reaction.

Word equation

A chemical equation that uses the names of substances rather than their formulas.

Formula equation

A chemical equation that uses chemical formulas to represent substances.

Exothermic

A reaction that releases energy (as heat or light) to the surroundings.

Endothermic

A reaction that absorbs energy from the surroundings.

Combustion

A chemical reaction with oxygen that releases heat and often light; typically involves hydrocarbons.

Respiration

The process of releasing energy from glucose using oxygen.

Corrosion

Deterioration of a metal due to a reaction with its environment, often involving oxygen.

Hydrocarbons

Compounds made of hydrogen and carbon; commonly used as fuels.

Photosynthesis

Process by which plants use light energy to convert carbon dioxide and water into glucose and oxygen.

Dissolution

The process of a solid dissolving in a liquid; can be endothermic (absorbs heat) as in some cold packs.

Ammonium nitrate (NH4NO3)

A solid that dissolves in water; dissolution absorbs heat (endothermic) and is used in instant cold packs.

Ammonium hydroxide (NH4OH)

A solution formed in some dissolution reactions; listed as a product in the endothermic equation with ammonium nitrate and water.

Nitric acid (HNO3)

A liquid product in the dissolution example with ammonium nitrate and water.

Water (H2O)

A liquid used as a solvent and a reactant in various reactions (e.g., ammonium nitrate dissolution) or a product in combustion/biochemical reactions.

Oxygen (O2)

A reactant commonly involved in exothermic reactions such as combustion.

Magnesium oxide (MgO)

A solid product formed when magnesium reacts with oxygen in a combustion reaction.

Octane (C8H18)

A hydrocarbon fuel used in combustion example; formula is C8H18.

Carbon dioxide (CO2)

A gas produced in combustion reactions (e.g., octane + oxygen → CO2 + H2O).