Select the incorrect statement among the following:

• O₃ is used as germicide for purification of air

• In O₃, O-O bond length is identical with that of molecular oxygen

• O₃ molecule is angular in shape.

• O₃ is an oxidising agent

Write with a balanced chemical equation how gypsum is used for the conversion of ammonia into ammonium sulnate without using H₂SO₄ ?

Sodium pyrophosphate is represented by which of the following formula ?

• Na₂P₂O₄

• Na₄P₂O₅

• Na₄P₂O₇

• Na₂P₂O₅

The starting material used in Solvay's process  are

• sodium sulphate

• brine solution

• carnallite

• all of the above

455.

Which one of the following can produce hydrogen when treated with metallic sodium?

• (CH₃)₂NH

• CH₃NH₂

• C₆H₅NH₂

• CH₃CONH₂

The first ionisation potential of Na, Mg, Al and Si are in the order

• Na <Mg>  Al <Si

• Na> Mg> Al> Si

• Na < Mg< Al> Si

• Na> Mg> Al<Si

The total number of protons in 10g of calcium carbonate is (N₀ = 6.023 x 10²³):

• 3.01 × 10²⁴

• 4.06 × 10²⁴

• 2.01 × 10²⁴

• 3.02 × 10²⁴

Which of the oxides does not react with both of an acid and alkali, is ?

• ZnO

• SnO₂

• Al₂O₃

• BeO

Bleaching action of bleaching powder is due to the liberation of

• O₂

• OCl^-

• Cl₂

• Cl^-

Which of the following is a false statement ?

• Fluorine is more electronegative than chlorine

• Nitrogen has greater IE₁ than oxygen

• Lithium is amphoteric

• Chlorine is an oxidising agent