7.2.2—Names and formulas of the common alkalis
- Syllabus
- 9701–2028–2029
- Objective
- 7.2.2
- Level
- AS
Common acids and alkalis are identified by formula and ion released
Common acids include hydrochloric acid HCl, nitric acid HNO₃ and sulfuric acid H₂SO₄. Common alkalis are soluble bases such as sodium hydroxide NaOH, potassium hydroxide KOH and aqueous ammonia NH₃(aq).
In water, acids increase hydronium concentration; soluble alkalis provide or generate hydroxide ions. Formula and state determine what particles are present.
HNO₃(aq) dissociates to H⁺/H₃O⁺ and NO₃⁻; NaOH(aq) provides Na⁺ and OH⁻. Their neutralisation produces water and a salt.
“Strong” and “concentrated” are different. Strength describes ionisation; concentration describes amount per volume.
ConceptA-Level CAIE Chemistry AS