Substances can exist in three states: the solid state, the liquid state and the gaseous state. Some substances can exist in all three states but others exist only in one state. It is impossible, for example, to melt an egg shell or a sea shell ~ the calcium carbonate that makes them up can only exist as a solid
One of the most interesting substances is water. Water has a large temperature range of which it is liquid ~ from just over 0 degrees Celsius to just under 100 degrees Celsius. It can absorb a lot of heat energy without changing temperature very much.
At 100 degrees Celsius, water boils and become steam, a colourless gas. At zero degrees Celsius, water turns to ice, and becomes a solid. Interestingly, ice is less dense than water, and the solid state floats on the liquid state ~ which is why there are icebergs.
Some substances pass from the solid state to the gaseous state without becoming a liquid in between. Potassium permanganate is one compound that does this ~ the purple solid just 'fumes' as it changes into a gas. This process is called sublimation.
One of the most interesting substances is water. Water has a large temperature range of which it is liquid ~ from just over 0 degrees Celsius to just under 100 degrees Celsius. It can absorb a lot of heat energy without changing temperature very much.
At 100 degrees Celsius, water boils and become steam, a colourless gas. At zero degrees Celsius, water turns to ice, and becomes a solid. Interestingly, ice is less dense than water, and the solid state floats on the liquid state ~ which is why there are icebergs.
Some substances pass from the solid state to the gaseous state without becoming a liquid in between. Potassium permanganate is one compound that does this ~ the purple solid just 'fumes' as it changes into a gas. This process is called sublimation.