31.

Gypsum is

• CaSO₄·H₂O

• CaSO₄·2H₂O

• 2CaSO₄·2H₂O

• CaSO₄

Solubility of which among the following substances in water increases slightly with rise in temperature?

• Potassium bromide

• Potassium chloride

• Potassium nitrate

• Sodium nitrate

When potassium is reacted with water which compound(s) is are formed preferentially?

• K₂O

• KO₂

• Both K₂O and KO₂

• K₂O₂

The solution which does not produce precipitate when treated with aqueous K₂CO₃ is

• BaCl₂

• CaBr₂

• MgCl₂

• Na₂SO₄

The second ionisation enthalpy of which of the following alkaline earth metals is the highest?

• Be

• Ba

• Mg

• Ca

Potassium dichromate belongs to which crystal system?

• Tetragonal

• Orthorhombic

• Triclinic

• Hexagonal

Which one of the following is an incorrect statement?

• O₃ oxidises PbS to PbSO4

• O₃ oxidises nitric oxide to nitrogen dioxide

• O₃ oxidises aqueous Kl at pH = 9.2

• The two oxygen-oxygen bond lengths in O₃ are different

In Solvay process of manufacture of sodium carbonate, the by-product is

• NH₄Cl

• NaHCO₃

• CaCl₂

• CO₂

Among the following compounds, the one that gets hydrolysed to form metallic hydroxide, hydrogen peroxide and oxygen is

• Na₂O

• Na₂O₂

• Li₂O

• KO₂

The alkaline earth metal with the least density value is

• Mg

• Be

• Sr

• Ca