Salt is an ionic compound that contains a cation (from base) and an anion (from acid).
It is present in large quantities in seawater, where it is the main mineral constituent. Salt is important for animal life and saltiness is one of the basic human tastes. Salt is an ionic compound that has a cation other than H and an anion other than OH and is obtained along with water in the neutralization reaction between acids and bases.
Examples: NaCl, CuCl2, etc.
NaOH + HCl → NaCl + H₂O
2KOH + H₂SO4 → K₂SO4 + 2H₂O
Ca(OH)₂ + 2HNO₃ → Ca(NO₃)₂ + 2H₂O
CaO + H₂SO₄ → CaSO₄ + H₂O
KOH + HNO₃ → KNO₃ + H₂O
BaCO₃ + 2HCl → BaCl₂ + CO₂ + H₂O
H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O
These are salts formed by the direct combination of a metal cation with a non-metal anion.
Sodium chloride (NaCl), potassium nitrate (KNO₃), calcium sulphate (CaSO₄).
Also known as hydrogen salts, acid salts are formed when an acid partially replaces the hydrogen ions with a metal cation.
Sodium dihydrogen phosphate (NaH₂PO₄), potassium hydrogen sulphate (KHSO₄).
Basic salts are formed when a metal hydroxide reacts with an acid, resulting in the formation of a salt and water.
Basic lead carbonate (PbCO₃·Pb(OH)₂), basic copper sulfate (CuSO₄·3Cu(OH)₂).
A buffer is a solution that resists changes in pH when small amounts of acid or base are added to it. It helps to maintain the pH of a solution relatively stable, even with the addition of acidic or basic substances. Buffers are essential in various chemical and biological processes to ensure the stability and functionality of systems that are sensitive to changes in acidity or alkalinity.
A buffer typically consists of a weak acid and its conjugate base or a weak base and its conjugate acid. When an acid is added to the buffer solution, the weak base component of the buffer reacts with the acid, neutralizing it. Similarly, when a base is added, the weak acid component of the buffer neutralizes the base. This allows the buffer to minimize changes in pH and keep the solution within a certain pH range.