271.

Electronic configuration of only one p-block element is exceptional. One molecule of that element consists of how many atoms of it?

• One

• Two

• Three

• Four

Which oxyacid of sulphur contains S-S single bond?

• Oleum

• Marshall's acid

• Dithionic acid

• Thiosulphuric acid

Which among the following group 15 element forms most stable pentavalent compound?

• Phosphorus

• Antimony

• Bismuth

• Arsenic

What is the basicity of orthophosphorous acid?

• One

• Two

• Three

• Four

Which oxoacid of sulphur contains S-S bond in its structure?

• Disulphurous acid

• Disulphuric acid

• Perdisulphuric acid

• Hydrosulphurous acid

Which halogen forms an oxyacid that contains the halogen atom in tripositive oxidation state? 

• Fluorine

• Chlorine

• Bromine

• Iodine

Identify the compound, in which phosphorus exists in the oxidation state of +1.

• Phosphonic acid (H₃PO₃)

• Phosphinic acid (H₃PO₂)

• Pyrophosphorus acid (H₄P₂O₅)

• Orthophosphoric acid (H₃PO₄)

In preparation of sulphuric acid from sulphur dioxide in lead chamber process. What substance is used as a catalyst?

• Manganese dioxide

• Vanadium pentoxide

• Nitric oxide

• Raney nickel

Which halogen has the highest value of negative electron gain enthalpy?

• Fluorine

• Chlorine

• Bromine

• Iodine

Freon 12 is manufactured from CCl₄ by

• Wurtz reaction

• Swarts reaction

• Fittig reaction

• Wurtz-Fittig reaction