Matter is anything that occupies space and has mass.
Mass is what matter is made up of.
Matter exists in three states commonly known as solids, liquids and gases (but there is little known state called plasma).
The different states of matter have different characteristics in regard to shape, volume and mass.
Heat affects matter, for example water.
Heat is the amount of warmth in matter.
The amount of heat can be estimated by change in temperature.
The higher the temperature the more heat a body has.
The effect of heat in matter can be looked at from two points, when heat is absorbed or when heat is released by the matter.
When solids are heated the following things may take place:
1. Solid expands when heated as they gain heat. Because of this Railway tracks has gaps for expansion.
Railway tracks will expand on hot days if no gap this is very dangerous, train can derail and endanger passengers as well as destroy goods.
Bridges have fitted rollers to allow for expansion and contraction, allow bridge to slide over the rollers smoothly when expanded.
Overhead cables and telephone lines are fitted to hang loosely.
2. The solid melts and becomes liquid when heated further.
The solid contracts when cooled as the loose heat.
Liquids can either change to solids or gas when exposed to heat.
1. Liquids increase in size when heated they are said to have expanded.
Pipes carrying water or steam are looped at intervals to allow for expansion. If not the pipes will burst
Coca Cola bottlers need to allow space when filling up their bottles or cans .No allowance will caused the bottles or cans to burst.
2. When cooled, liquids decrease in size they are said to have contracted.
3. When liquids are heated to a certain temperature they change to gas they evaporate or vaporise.
4. When liquids are exposed to very low temperatures the liquid freezes and becomes solid. When water freezes it expands.
1. When heated gases expand.
Hot balloon uses the expansion of gases .Filled with heated air. As volume of air increases (expansion), the density of air decreases.
Warm air less dense this it rises and carries the balloon upwards.
Baking bread or cake, baking powder is added.
Carbon dioxide gas is released from the baking powder expands when heated causing the dough to rise.
2. When cooled gases contract.
3. Gas condenses to become liquid when cooled to very low temperatures.