Heat of Reactions, Acids and Bases, Reaction Rates

Reaction Rate: Change in concentration per unit time.

Catalyst: Substance that increases rate without being consumed.

Collision Theory: Reactions occur when particles collide with enough energy.

Arrhenius Acid: Produces H⁺ ions in water.

Arrhenius Base: Produces OH⁻ ions in water.

Brønsted-Lowry Acid: Proton donor.

Brønsted-Lowry Base: Proton acceptor.

Strong Acid/Base: Completely ionises in water.

Weak Acid/Base: Partially ionises in water.

Ampholyte: Substance acting as both acid and base (e.g. water).

Conjugate Acid/Base Pair: Two species differing by one proton.

Hydrolysis: Reaction of a salt with water.

Neutralisation: Reaction of acid with base to form water and salt.

pH Scale: Scale from 0 to 14 indicating acidity/alkalinity.

Equivalence Point: Point in titration where moles of acid = moles of base.

End Point: Point in titration where the indicator changes colour.

Exothermic Reaction: Releases energy to the surroundings (ΔH < 0).

Endothermic Reaction: Absorbs energy from the surroundings (ΔH > 0).

Activation Energy (Ea): Minimum energy needed to start a reaction.

Heat of Reaction (ΔH): Energy change during a reaction.

Activated Complex: Unstable intermediate formed during a reaction.