DEFINE & Calcification of SALT? | THE PROPERTIES & USES OF SALT IN WET PROCESSING OF TEXTILE?

SALT:

When Hydrogen atom of acid is fully or partly replaced by the metal or metal like reactive radical, then the compound which is found is known as salt.

Example: NaCl, KNO3, CaCl2 etc.

Classification of SALT:

Salts are classified into following six types according to the construction:

1. Normal salt: The salt which is produced by replacing the Hydrogen atom of acid by metal or metal like active radicals is known as normal salt. Ex.: ZnSO4, KNO3, NaCl etc.

2 Na + 2 HCl = 2 NaCl + H2.

2. Acid salt: The salt which is produced by replacing the Hydrogen atom partly by metal like active radicals is known as acid salt. Ex.: NaHSO4.

NaOH + H2SO4 = NaHSO4 + H2O.

3. Basic salt:  If the amount of acid to produce normal salt with certain amount of base is less than the salt is called basic salt. Ex.: [CaCO3.Ca(OH)2].

4. Mixed salt: The salt which is produced by replacement of more than one Hydrogen atom by more than one different types of metals is called the mineral salt. Ex.: NaKCO3.

5. Couple salt: When two normal salts are mixed together in their soln at same ratio, then thissalt is called couple salt.

Ex.: [K2SO4.Al2(SO4)3.24H2O].

6. Complex salt: If two different normal salts are mixed at a certain ratio, where the mixed compound has the properties different from the two normal salts, then the salt, which is produced is called complex salt.

Ex.: [K4Fe(CN)6].

Properties:

1. The test & color of different salts are different.

2. The colors of salts are generally white, green, blue, yellow, red etc.

3. The solubility of different salts are different.

4. In water, it is ionized & produce +ve& -ve ion. NaCl (dissolved in water) = Na+ + Cl-

5. Each salt contains an acidic & a basic radical.

USES OF SALT IN WET PROCESSING OF TEXTILE:

1. Na2SO4 is used for the finishing of cotton is also for dyeing of direct & Sulphur dyes.

2. NaHSO4 is used for washing of silk & wool.

3. Na2SO4 is used to remove the color of silk, wool & cotton.

4. NaOCl is used in bleaching.

5. Ca(OCl)Cl is used in cotton bleaching.

6. NaClO3 is used in bleaching, dyeing & printing.

7. Na2S is used to make the solution of Sulphur dye