31.

The electrophile involved in the nitration of benzene is :

• NO₂

• NO₂⁺

• NO

• NO₂^-

The correct order of ease of dehydration of following is :

• I > II > III

• III > II > I

• I > III > II

• III > I > II

What is the oxidation number of chlorine in ClO₃^- ?

• + 5

• + 3

• + 4

• + 2

How many electrons are involved in oxidation of KMnO₄ in basic medium ?

• 1

• 2

• 5

• 3

Which of the following is not an ore of magnesium ?

• Magnesite

• Dolomite

• Gypsum

• Carnalite

Industrial name for H₂S₂O₇ is :

• Pyrosulphuric acid

• Marshall's acid

• Oleum

• all of the above

I₂ dissolves in KI solution due to the formation of :

• KI₂ and I^-

• K⁺ , I^- and I₂

• KI₃^-

• none of these

In Mc Arthur Forest method , silver is extracted from the solution of Na[Ag(CN)₂] by the use of :

• Fe

• Mg

• Cu

• Zn

Which of the following is anhydride of perchloric acid ?

• Cl₂O₇

• Cl₂O₅

• Cl₂O₃

• HClO

Which of the following sulphides is yellow in colour ?

• CuS

• CdS

• ZnS

• CoS