- No. iv. How many water of crystallizations are present in CuSO4.5H2O and CaSO4.2H2O?
Answer. CuSO4. 5H20 consists of 5 molecules of water of crystallization.
CaSO4. 2H2O consists of 2 molecules of water of crystallization.
- No. v. Name the type of reaction that takes place between an acid and a metal. Which gas would evolve in the reaction? Explain with an example.
Answer. The reaction which takes place between an acid and a metal is called direct displacement reaction. Because H+ ion of the acid is replaced with the metal and hydrogen gas is evolved during the reaction. For example,
2HCl(aq) Mg(s) —————> MgCl2(aq) + H2(g)
Test Yourself 10.5 (TYPES OF SALTS)
- No. i. Name the types of salts.
Answer. There are six types of salts:
(1) Normal salts (2) Acidic salts (3) Basic salts (4) Double salts (5) Mixed salts (6) Complex salts
- No. ii. H3PO4 is a weak acid but its salt (Na3Po4) with strong base NaOH is neutral Explain it.
Answer. A salt formed by the total replacement of ionizable H+ ions of an acid by a positive metal ion is called neutral salt. Although H3PO4 is a weak acid, but as its all ionizable H+ ions has been replaced by sodium metal it is called neutral salt.
H3PO4(aq) + 3NaOH(aq) ———> Na3PO4(aq) + 3H2O(1)
- No. iii. How the basic salts turn into normal salts? Explain with an example.
Answer. Basic salts are formed by the incomplete neutralization of a poly hydroxyl base by an acid.
Zn(OH) 2(aq) + HNO3(aq) —————> Zn(OH)NO3(aq) + H2O
These salts consist of replaceable hydroxyl (OH-) ions. Hence they further react with acids to form normal salts that do not consist of replaceable hydroxyl (OH-) ions.
Zn(OH)NO2(aq) + HNO3(aq) ————> Zn(NO3)2(aq) + H2O(1)