Sodium chloride is an ionic compound with the chemical formula NaCl. It is a colorless cubic crystal or fine crystalline powder and tastes salty.
The appearance is a white crystal and its source is mainly sea water, which is the main component of table salt. Soluble in water, glycerin, slightly soluble in ethanol (alcohol), liquid ammonia, insoluble in concentrated hydrochloric acid.
Impure sodium chloride is deliquescent in air.
The stability is relatively good. Its aqueous solution is neutral.
Industrially, the method of electrolytically saturated sodium chloride solution is generally used to produce hydrogen, chlorine and caustic soda (sodium hydroxide) and other chemical products (commonly called Chlor-alkali industry).
Important Properties of Common Salt
English name: Sodium Chloride
Molecular formula: NaCl
Molecular weight: 58.44280
Physical Properties :-
It is a colorless crystal solid material.
It is highly soluble in water.
Its taste is salty.
It cracks when heated.
When it left open in the air, it exhales after getting moisture. This happens due to the impurity of magnesium chloride in the salt.
Its solution is neutral towards litmus.
The density of pure sodium chloride is 2.17 and the melting point is 800°C.
NaCl is dispersed in alcohol to form colloids. Its solubility in water is reduced by the presence of hydrogen chloride and it is almost insoluble in concentrated hydrochloric acid.
Chemical Properties of Sodium Chloride
The crystals of sodium chloride form stereo symmetry. In its crystal structure, the larger chloride ions form the densest packing in the cube and the smaller sodium ions fill the octahedral gap between the chloride ions.
Each ion is surrounded by six other ions. This structure is also found in many other compounds, called sodium chloride type structure or stone salt structure.
Reaction with acids :- On heating sodium chloride with concentrated sulfuric acid (H2SO4), hydrochloric acid (HCl) is formed.
NaCl + H2SO4 → NaHSO4 + HCl
NaHSO4 + NaCl → Na2SO4 + HCl
Reaction with silica (sand) :– On heating sodium chloride with silica (SiO2) at high temperature, sodium silicate is formed.
2NaCl + SiO2 + H2O → Na2SiO3 + 2HCl
Reaction with ammonia :- By passing ammonia and carbon hydroxide gas in a concentrated solution of salt, sodium bicarbonate (NaHCO3) and ammonia chloride (NH4Cl) are formed.
NaCl + NH3 + CO2 + H2O → NaHCO3 + NH4Cl
Reaction with manganese dioxide : – Chlorine gas (Cl2) is obtained when it is heated with manganese dioxide and sulfuric acid. Industrial production of chlorine is done by this process.
2NaCl + MnO2 + 3H2SO4 → MnSO4 + 2NaHSO4 + 2H2O + Cl2
Reaction with silver nitrate :- On reacting with silver nitrate solution gives white precipitate of silver chloride.
NaCl + AgNO3 → NaNO3 + AgCl