Acid Base Alkali pH scale Indicator Universal indicator Litmus paper Neutralisation Salt Word equation Symbol equation Concentrated acid Dilute acid Collision theory Pop test Limewater test Metal + acid reaction Carbonate + acid reaction Hydrochloric acid (HCl) Sulfuric acid (H₂SO₄) Nitric acid (HNO₃) Sodium hydroxide (NaOH) Calcium carbonate (CaCO₃) Potassium hydroxide (KOH) Vinegar Citric acid Ammonia Hydrogen ion (H⁺) Hydroxide ion (OH⁻)