24. i) Explain softening of permanent hardness of water by Calgon's process.
ii) Give an example of ionic hydride.
Answers
Answer:
Calgon is a trade name of a complex salt, sodium hexametaphosphate, (NaPO
3
)
6
. It is used for softening hard water. Calgon ionizes to give a complex anion:
(NaPO
3
)
6
or Na
2
(Na
4
P
6
O
18
)→2Na
+
+Na
4
P
6
O
18
2−
The addition of Calgon to hard water causes the calcium and magnesium ions of hard water to displace sodium ions from the anion of Calgon.
Ca
2+
+Na
4
P
6
O
18
2−
→2Na
+
+CaNa
2
P
6
O
18
2−
This results in the removal of calcium and magnesium ions from hard water in the form of a complex with Calgon. The water is softened and sodium ions are released into water.
Answer:
Calgon is a trade name of a complex salt, sodium hexametaphosphate, (NaPO
3
)
6
. It is used for softening hard water. Calgon ionizes to give a complex anion:
(NaPO
3
)
6
or Na
2
(Na
4
P
6
O
18
)→2Na
+
+Na
4
P
6
O
18
2−
The addition of Calgon to hard water causes the calcium and magnesium ions of hard water to displace sodium ions from the anion of Calgon.
Ca
2+
+Na
4
P
6
O
18
2−
→2Na
+
+CaNa
2
P
6
O
18
2−
This results in the removal of calcium and magnesium ions from hard water in the form of a complex with Calgon. The water is softened and sodium ions are released into water.
Explanation: