Plaster of Paris is a white powder of formula :

• ${\mathrm{CaSO}}_4.\frac{1}{2}{\mathrm{H}}_2\mathrm{O}$

• CaSO₄.2H₂O

• CaSO₄.H₂O

• CaSO₄.$\frac{3}{2}$H₂O

CaC₂ + N₂ → A, product A is

• CaCN₂

• CaCN₂ and C

• CaCN₂ + N₂

• None of these

Calcium formate on distillation gives :

• HCOOH

• CH₃COOH

• CH₃CHO

• HCHO

Baking powder contains :

• NaHCO₃, Ca(H₂PO₂)₂ and starch.

• NaHCO₃, Ca(H₂PO₂)₂ 

• NaHCO₃ and starch.

• NaHCO₃

Estimation of calcium and magnesium is done by:

• EDTA

• oxalate

• phosphate

• none of these

Which of the following does not react with sodium metal?

• (CH₃)₂O

• CH₃CH₂OH

• CH₃COOH

• C₆H₅OH

The element which on burning in air gives peroxide is

• lithium

• sodium

• rubidium

• caseium

Which compound is used in photography?

• Na₂SO₅

• Na₂S₂O₈

• Na₂S₂6

• Na₂S₂O₃

139.

Sodium thiosulphate is a

• reducing agent

• oxidising agent

• complexing agent

• bleaching agent

Plaster of Paris on making paste with little water sets to hard mass due to formation of

• CaSO₄

• CaSO₄.1/2 H₂O

• CaSO₄ H₂O

• CaSO₄.2H₂O