Chemistry Test Grade 9

The Particle Theory of Matter

Enables us to explain how matter behaves; the states of matter, changes of sate, diffusion and how temperature affects diffusion.

Matter

Anything made up of atoms

The first point of particle theory is

Matter is made up of tiny particles

The second point of particle theory is

All particles of one substance are identical. Different types of matter are made of different particles.

The third point of particle theory is

The particles in matter are constantly in motion. Increasing the temperature increases the amount of motion.

The fourth point of particle theory is

The particles in matter are attracted to each other. This attraction is stronger when particles are closer together.

Solids

Particles are very close and attracted to each other

Liquids

particles are close together but they can tumble past each other

Gas

Particles are very far apart

Solid to Liquid

melting

Liquid to Solid

Freezing

Liquid to Gas

vaporization

Gas to Liquid

condensation

Solid to Gas /Gas to Solid

sublimation

A substance that undergoes all six changes of state in nature...

H2o

When heat energy is added...

particles move more quickly which cause melting, vaporization and sublimation (solid to gas)

When heat energy is removed...

particles move more slowly which cause freezing, condensation and sublimation (gas to solid)

Example of change in state

It would be better to put an ice pack on top of drinks in a cooler since cold air is heavy.

Atom or Element

1 element only (maybe two or more atoms of the same element bonded together) (e.g.: hydrogen)

molecule or compound

2 or more elements bonded (or stuck) together and the elements could be the same or different (e.g: Water H2o)

Homogeneous Mixture

One or more substance dissolved in another (the prefix homo means the same)

Solvent

Does the dissolving

Solutes

Gets dissolved

Heterogeneous mixture

The different parts of a heterogeneous mixture can easily be seen and picked out. E.g: trail mix (hetero means different)

density

How tightly packed matter is

From less dense to most dense

Gas, liquid, solid

Formula to calculate density

Density = mass/volume

Formula to calculate mass

Mass = Density x Volume

Formula to calculate volume

mass/density

physical properties

The characteristics of a substance that could be observed or measured

Can matter be separated by physical means?

By using a physical property such as size, color, texture, mass, weight and/or density

chemical properties

determined when a substance is changed and a new substance is produced

examples of chemical properties

flammability, acidity, ability to rust, radioactivity, reactivity, ability to oxidize, half life, heat of combustion