Acid reactions and neutralisation quantities

Acids react with many metal oxides and hydroxides to form a salt and water. Their central ionic changes include 2H++O2−→H2​O within an oxide and H++OH−→H2​O for dissolved strong acid and hydroxide. Neutralisation releases heat. Carbonates and hydrogencarbonates additionally produce carbon dioxide: CO32−​+2H+→CO2​+H2​O, while HCO3−​ needs one H+.

Write the correct salt formula from ion charges before balancing. For quantitative work, convert acid or base quantities to moles and apply the balanced coefficient ratio. A diprotic acid can require twice as much hydroxide per mole as a monoprotic acid when fully neutralised. A stated excess reagent remains after the limiting reagent is consumed. Use final solution volumes and the specified complete-neutralisation endpoint in calculations.

Watch out: The ratio depends on the balanced equation and how many protons are neutralised.