Question

1) Which of the following statements is incorrect?
Plaster of Paris is used to ornate designs on walls and ceilings.
(b) On heating gypsum above 373 K, CaS04 is obtained. (c) Dead burnt plaster is
CaS04.2H20.
(d) Setting of plaster is due to its hydration into gypsum.
(1)​

Answer 1

Answer:

b. On heating gypsum above 373k , caso4 is obtained

Answer 2

(b). On heating gypsum above 373 K, CaS04 is obtained, which is the answer.

Explanation:

On checking the given options , we get that:-

(a). It is a correct statement that Plaster of Paris is used to ornate designs on walls and ceilings.

(c). It is a correct statement that Dead burnt plaster is  CaS04.2H20.

(d). It is a correct statement that  Setting of plaster is due to its hydration into gypsum.

But,

(b). It is not a correct statement that On heating gypsum above 373 K, CaS04 is obtained because When gypsum is heated above 373k Plaster of Paris is formed.

Hence, (b).  On heating gypsum above 373 K, CaS04 is obtained. is the answer.