The chemical formula of Plaster of Paris is:

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

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

3. ${\mathrm{CaSO}}_4.{\mathrm{H}}_2\mathrm{O}$

4. 3CaSO₄.H₂O
$\mathrm{}$

The number of crystal water in Gypsum, Plaster of Paris and Epsom salt respectively are-

1. 2, 0.5, 7                                             

2. 7, 2, 1

3. 7, 0.5, 2                                             

4. 3, 4, 2

A compound X on heating gives a colourless gas. The residue is dissolved in water to obtain Y. Excess $C{O}_2$ is bubbled through an aqueous solution of Y, and Z is formed. Z on gentle heating gives back X. The compound X is-

1. ${\mathrm{CaCO}}_3$                                           

2. ${\mathrm{Na}}_2{\mathrm{CO}}_3$

3. ${\mathrm{CaSO}}_4.2{\mathrm{H}}_2\mathrm{O}$                                 

4. ${\mathrm{K}}_2{\mathrm{CO}}_3$

Potassium carbonate cannot be prepared by the Solvay process because -

 An active ingredient in bleaching powder that aids in the bleaching action is:

1.  $\mathrm{Ca}{\left(\mathrm{OCl}\right)}_2$

2.  ${\mathrm{CaO}}_2\mathrm{Cl}$

3.  ${\mathrm{CaCl}}_2$

4.  ${\mathrm{CaOCl}}_2$

A Brine solution on electrolysis will not give : 

1.  NaOH

2.  ${\mathrm{Cl}}_2$

3.  ${\mathrm{H}}_2$

4.  ${\mathrm{O}}_2$

Gypsum on heating can change to :

1. Orthorhombic form.

2. Plaster of paris.

3. Dead plaster.

4. All of the above.

Magnesia can be prepared by -

1. Burning Mg in air.

2. Heating hydroxide, nitrate, sulphate or carbonate of magnesium.

3. Heating Mg in steam.

4. All of the above.

The suspension of slaked lime in water is known as -

1. Limewater.

2. Quicklime.

3. Milk of lime.

4. Aqueous solution of slaked lime.

Quick lime is heated with silica to give:

1. CaSiO₃

2. CaSiO₄

3. CaSiO

4. Ca(SiO)₃