Chemical formula- H2O
State at room temperature- Liquid
Melting point- 0oC
Boiling point- 100oC
Water- good solvent and a range of substances will dissolve in it.
What happens when a sugar lump dissolves in water?
When the sugar dissolves...
-The moving water molecules crash into the sugar particles
-The sugar particles then break away from the crystal and into the water -The sugar and water particles then mix and diffuse evenly throughout.
Copper sulphate- blue crystals, hydrated because they have water trapped within them. When they are heated this water evaporates, the crystals become dehydrated and turn white.
Equation for this Reaction.
CuSo4 5H2O ---> CuSo4 + 5H2O
Solute- Solid which is dissolving
Solvent- liquid in which the solute dissolves
Solution- the solute and solvent mixed together
Sodium hydroxide- Soluble
Copper Oxide- insoluble
Calcium hydroxide- Insoluble
Silver iodide- insoluble
Aluminium nitrate- soluble
Most ionic substances will dissolve in water but covalent substances usually wont dissolve.
Solubility of a solute = mass of a solid required to a saturate 100g of water at a particular temperature.
2g potassium chlorate dissolves in 20g water at 28oC what is its solubility?
2 x 100/20 = 10.0g potassium chlorate/100g water
4g potassium sulphate dissloves in 30g water at 50oC what is its solubilty?
4 x 100/30 = 13.33g potassium sulphate/100g water
30g sodium chloride dissolves in 75g water at 10oC what is its solubility?
30 x 100/75 = 40g sodium chloride/100g water
Solubility Of Gases
Carbon dioxide is the gas which is dissolved in fizzy drinks to make the fizz.
What happened when you placed sprite in a boiling tube and gave it a shake? The sprite fizzed up.
What happened after you heated the sprite then gave it a shake again? If fizzed just a little
Carbon dioxide is more soluble in cold liquid.
The solubility of gases...