Acids and alkalis and neutralisation reactions:

Acids and Alkalis

Alkalis are soluble in water-bases are insoluble alkalis

Acid-proton donor

Base-proton acceptor

Neutralisation reaction: Acid + Base → salt + water

Common neutralisation reaction:

HCl + NaOH → NaCl + H20

Common acids:

Hydrochloric acid → HCl

Sulfuric acid → H2SO4

Nitric acid → HNO3

Common bases:

Sodium hydroxide → NaOH

Calcium carbonate → CaCO3

Neutralisation reactions:

Metal oxides + acid → salt + water

Metal hydroxides + acid → salt + water

Metal carbonates + acid → salt + water + carbon dioxide

The acid always contains the negative ion

The base always contains the positive ion

All the salts made are soluble in water

All you need to do is react an acid with an insoluble base- a metal hydroxide, oxide or carbonate

  1. Heat dilute acid in beaker with bunsen burner

  2. Keep adding the insoluble base a little at a time

  3. Add until base stops disappearing - in excess = neutralised all the acid

  4. Filter out the excess base using filter paper and funnel

  5. Left is the dissolved form of the soluble salt

  6. Gently heat up the filtered solution to evaporate off some water- don’t heat too much and risk damaging the salt

  7. Stop heating and leave to cool once crystals start to form

  8. Filter out crystals

  9. Dry them by dabbing with filter paper

Flashcards on Acids and Alkalis

  • Acids: Substances that donate protons (H+ ions).

  • Alkalis: Soluble bases, which accept protons in reactions.

  • Neutralisation Reaction: The chemical reaction where an acid reacts with a base to produce a salt and water.

  • Common Neutralisation Reaction: HCl + NaOH → NaCl + H₂O.

  • Common Acids:

    • Hydrochloric acid (HCl)

    • Sulfuric acid (H₂SO₄)

    • Nitric acid (HNO₃)

  • Common Bases:

    • Sodium hydroxide (NaOH)

    • Calcium carbonate (CaCO₃)

  • Types of Neutralisation Reactions:

    • Metal oxides + acid → salt + water

    • Metal hydroxides + acid → salt + water

    • Metal carbonates + acid → salt + water + carbon dioxide

  • Formation of Salt: The acid contains the negative ion, and the base contains the positive ion.

  • Solubility: All salts made are soluble in water.

  • Preparation of Soluble Salt:

    1. Heat dilute acid in a beaker.

    2. Add insoluble base gradually.

    3. Filter out excess base once it stops disappearing.

    4. Evaporate water gently to crystallize the salt.

    5. Cool and filter out crystals, then dry.