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What is a solution?

Dissolving table salt in waterDissolving table salt in waterStir a teaspoon of table salt into a glass of water, and the salt disappears. However, tasting the water shows the salt is still there. It has dissolved. The crystals of salt have broken down into their individual atoms. These are too small to see and float about freely among the molecules of water. The liquid, known as the solvent, and the salt dissolved in it are together known as a solution.

The Dead Sea, a saturated salt solutionThe Dead Sea, a saturated salt solution

Dripping stalactitesDripping stalactites

Stalagmites and stalactites

Limestone is made of calcium carbonate, a mineral (a chemical that makes up rock) that dissolves easily in water. Water dripping from a cave roof leaves a tiny amount of the dissolved minerals behind as it falls.

Over time, these build up into limestone “icicles”, called stalactites. Stalagmites are mineral towers made from water dripping on to the floor from the stalactites above. 

Fizzy drinks are solutions of carbon dioxide, a gas, in water. The bubbles are small pockets of carbon dioxide that are released from the solution. The dissolved gas itself is not visible.

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