Density
Density is defined as the mass of an object (in kilograms) divided by the volume (length by breadth by depth, in metres3). For example, 1000kg of water occupies a volume of 1mx1mx1m, so its density is 1000kg/m3
Solids are not pourable and usually have fixed shape; liquids can be poured and take the shape of their container; gases easily can escape their container, unless there is a lid.
Dissolving: Mixing something with a liquid so that it becomes part of the liquid e.g. stirring sugar into tea
Soluble: Something which can be dissolved, especially in water
Solution: Liquid into which something has been dissolved
- Mass and weight
- Units e.g. kg, m, m3
- Mixing and making solutions (e.g. salt or sugar in water)
- Concentrations e.g. a solution of 100grams of salt in 1litre of water has a higher salt concentration than a solution of 100grams of salt in 10litres of water