Chemical Reactions Vocabulary

Vocabulary flashcards generated from the Chemical Reactions lecture notes, covering reaction types, energy profiles, rates of reaction, and precipitation rules.

Physical Change

A change in physical properties, such as position, shape, size, or state, where no new substances form.

Chemical Reaction

A process where new substances form through the breaking of bonds in reactants and the formation of new bonds in products.

Reactants

The starting substances in a chemical reaction whose bonds are broken.

Products

The new substances formed as a result of a chemical reaction.

Composition Reaction

A chemical reaction where two or more reactants join together to form a single product, following the general form $A + B \rightarrow AB$.

Decomposition Reaction

A chemical reaction where a single reactant breaks down into two or more products, following the general form $AB \rightarrow A + B$.

Combustion Reaction

An exothermic reaction occurring when a substance reacts rapidly with oxygen gas ($O_2$), resulting in burning or exploding.

Exothermic Reaction

A chemical reaction that releases energy to its surroundings, characterized by net energy released ($-\text{Δ}H$).

Endothermic Reaction

A chemical reaction that absorbs energy from its surroundings, characterized by net energy absorbed ($+\text{Δ}H$).

Activation Energy

The minimum energy needed to start a reaction by breaking reactant bonds.

Fire Triangle

A model illustrating the three essential components required for fire: fuel, oxygen ($O_2$), and heat.

Hydrocarbons

Fossil fuels built only out of hydrogen and carbon atoms, formed from the decomposition of organic material under pressure over millions of years.

Complete Combustion

Combustion occurring with an excess of oxygen, producing carbon dioxide ($CO_2$) and water ($H_2O$) as the only products.

Incomplete Combustion

Combustion occurring under non-optimal conditions (lack of oxygen or heat), producing poisonous carbon monoxide ($CO$) and carbon soot ($C$) alongside $CO_2$ and $H_2O$.

Single Displacement Reaction

A reaction where one ion displaces another in a compound, following the general form $AB + C \rightarrow CB + A$.

Spectator Ions

Ions that do not take part in a chemical reaction and remain dissolved in solution throughout the process.

Double Displacement Reaction

A reaction between two aqueous solutions where positive and negative ions exchange partners, following the general form $AB + CD \rightarrow AD + CB$.

Precipitate

An insoluble solid product that settles out of a liquid solution.

Precipitation Reaction

A double displacement reaction that generates an insoluble solid product that settles out of solution.

Solubility Chart

A reference guide used to check whether an ionic compound product is soluble or insoluble in water.

Rate of Reaction

A measure of how quickly reactants are converted into products in a chemical reaction.

Collision Theory

A theory stating that chemical reactions require collisions between reactant particles with both the right orientation and enough energy to break bonds.

Catalyst

A substance that speeds up the rate of a chemical reaction by holding reactants in the correct orientation and lowering activation energy, without being consumed.