all chemistry topics

Atom

The building block of matter made of protons, neutrons, and electrons

Proton

A positively charged particle found in the nucleus of an atom

Electron

A negatively charged particle found in shells around the nucleus

Valence electron

Electrons in the outermost shell

Ion

An atom or molecule with an electrical charge

Neutral

No charge

Ionic Compound

A neutral compound consisting of positive and negative ions held together by ionic bonds

Ionic Bond

Electrostatic attraction between positive and negative ions

Group

A vertical column of elements

What do elements in the same group have in common?

They have the same number of outer electrons, called valence electrons

Period

Horizontal row on the periodic table

What do elements in the same period have in common?

As you move across a period from left to right, each element adds one proton and one electron, changing properties from metal to non-metal

Reaction Rate

The speed at which a chemical reaction takes place

Successful Collision

A particle collision in the correct orientation and with enough energy for a reaction to occur

Frequency of Collisions

The number of particle collisions per second

Surface Area

The total outer area of a solid reactant exposed to a liquid or gas

What happens when an acid reacts with a solid?

When an acid reacts with a solid, a larger surface area means more particles are exposed. This allows more collisions to happen at the same time, which makes the reaction go faster

Kinetic Energy (Ek)

Energy due to motion; higher temperature increases kinetic energy and particle speed

What increases kinetic energy?

- More Ek = faster moving particles - Temperature increases kinetic energy of particles

Particle Collision Theory

Chemical reactions happen when reactant particles bump into each other

What are the requirements for the particle collision theory to occur?

- Must have enough speed (activation energy) - The right angle to break and make bonds

Acid

A substance that releases H+ ions in solution

Base

A substance that releases OH- ions in solution

H+

Hydrogen ion/proton

OH-

Hydroxide ion

pH

A measure of the acidity of a solution based on concentration of H+ ions relative to OH- ions

Neutral

Solution with equal concentrations of OH- and H+ ions

Concentration

The number of particles in a given volume, represented by square brackets

Neutralisation

A chemical reaction where an acid reacts with a base to form a neutral salt and water