U5: Electrochemistry (SCH4U)

Specific Heat Capacity

The amount of energy that is needed to raise the temperature of one gram of a substance by 1 C.

Thermodynamics

The study of energy and energy transfer.

System

The part of the universe that is begin studied and observed.

Surroundings

Everything else in the universe.

Temperature

The measure of the average kinetic energy of the particles that make up a substance or system.

Enthalpy

The total internal energy of a substance at a constant pressure.

Endothermic Reaction

A reaction that results in a net absorption of energy.

Exothermic Reaction

When more energy is released to form bonds then is used to break bonds.

Pauli Exclusion Principle

No two electrons in an atom have the same four quantum numbers.

Orbitals

Results from wave functions that give information about an electron's energy and location within an atom.

Ground State

The most stable energy state for any element.

Polar Covalent Bond

A covalent bond with an unequally shared pair of electrons between two atoms.

Hess's Law of Heat Summation

The enthalpy change of a physical or chemical process depends only on the beginning conditions and the end conditions. The enthalpy change is independent of the pathway of the process and the number of intermediate steps in the process.

Activation Energy

The minimum collision energy that is required for a successful reaction.

Transition State Theory

Used to explain what happens when molecules collide in a reaction.

Potential Energy Diagram

A diagram that charts the potential energy of a reaction against the progress of the reaction.

Transition State

The "change over point" of a reaction.

Activated Complex

A transitional species that is neither product nor reactant. It has partial bonds and is highly unstable.

Reaction Mechanism

A series of steps that make up an overall reaction.

Elementary Reaction

Involves a single molecular event, such as a simple collision between atoms, molecules or ions.

Reaction Intermediates

Molecules (or atoms or ions) that are formed in an elementary reaction and consumed in a subsequent elementary reaction.These are essential for the reaction to take place.

Molecularity

Refers to the number of reactant particles that are involved in an elementary reaction.

Le Chatelier's Principle

A dynamic equilibrium tends to respond so as to relieve the effect of any change in the conditions that affect the equilibrium.

Common Ion Effect

Involves adding an ion to a solution in which the ion is already present in solution.