Chemistry revision Topic 3: Reactions and Solubility (Reactions of aqueous…
Chemistry revision Topic 3: Reactions and Solubility
Reactions of aqueous solutions of acids
Hydrogen ions+hydroxide ions=water
Acid+metal oxide/metal hydroxide=salt+water
Acid+metal carbonate=metal salt+carbon dioxide+hydrogen
Lit splint causes squeeky pop if hydrogen is present
If you bubble gas through lime water, the solution will turn cloudy if carbon dioxide is in the gas
Mix the two mixtures together until excess. Filter the precipitate and bake this in an oven.
Only salt and water left in the beaker as precipitate is filtered out
Making soluble salts
Heat acid to speed up reaction, add base until excess, showing all the acid has neutralised
Filter excess so the salt isn't contaminated with base.
Heat soluble solution to evaporate some of the water, then leave it to cool.
Filter out of solution and dry (crystallisation).
Titration gives an exact measurement so the salt doesn't react with excess alkali
Needed as you don't know when the reaction has finished
Burette adds acid into dissolved alkali until changes colour
Repeat with the same amounts but without indicator so the salt won't be contaminated by the indicator
Just salt and water will remain as the alkali and acid would've completely reacted
Evaporate some water, then leave the solution to crystallise, then filter off the solid and dry it to be left with pure, dry salt