NEET 2013

$$KMnO_{4}$$ can be prepared from $$K_{2}MnO_{4}$$ as per the reaction $$3MnO_{4}^{2-} + 2H_{2}O \rightleftharpoons 2MnO_{4}^{-} + MnO_{2} + 4OH^{-}$$ The reaction can go to completion by removing $${OH}^{-}$$ ions by adding :

Reaction by which Benzaldehyde cannot be prepared :

Which of the following does not give oxygen on heating ?

A metal has a fcc lattice. The edge length of the unit cell is 404 pm. The density of the metal is 2.72 g $$cm^{-3}$$. The molar mass of the metal is : ($$N_{A}$$ Avagadro's constant = $$6.02 \times 10^{23} mol^{-1}$$)

Dipole - induced dipole interactions are present in which of the following pairs :

Roasting of sulphides gives the gas X as a by-product. This is a colorless gas with choking smell of burnt sulphur and causes great damage to respiratory organs as a result of acid rain. Its aqueoussolutionis acidic, acts as a reducing agent and its acid has never been isolated. The gas X is:

Some meat- directing substutients in aromatic substitution are given .Which one is most deactivating?

Nitrobenzene on reaction with $$\frac{conc.HNO_{3}}{H_{2}SO_{4}}$$ at 80 $$-100^\circ$$C forms which one of the following products?

A hydrogen gas electrode is made by dipping platinum wire in a solution of HCI of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of electrode would be ?

Which of the following is a polar molecule ?