31.

Energy of activation of an endothermic reaction is

• negative

• positive

• zero

• Cannot be predicted

Chlorine reacts with carbon disulphide in presence of I₂ catalyst to form

• CHCl₃

• CHI₃

• CCl₄

• C₂H₅Cl

The electronic configuration of P in H₃PO₄

• 1s² 2s², 2p⁶, 3s² 3p⁶

• 1s², 2s², 2p⁶ 3s²

• 1s², 2s² 2p⁶

• 1s², 2s², 2p⁶,3s² 3p³

The percentage composition by weight of an aqueous solution of a solute (molar mass 150) which boils at 373.26 K (k_b = 0.52) is

• 7

• 6

• 9

• 15

Solutions P, Q, R and S are respectively 0.1 M glucose, 0.05 M NaCl, 0.05 M BaCl₂ and 0.1 M AlCl₃.Which one of the following pairs is isotonic?

• P and Q

• Q and R

• P and S

• P and R

In which one of the following reactions, nitrogen is not reduced?

• NO₂ → NO${}_2^{-}$

• ${\mathrm{NO}}_3^{-} \to \mathrm{NO}$

• ${\mathrm{NO}}_3^{-} \to {\mathrm{NH}}_4^{+}$

• ${\mathrm{NH}}_4^{+} \to {\mathrm{N}}_2$

The coordination number and oxidation state of Cr in K₃[Cr(C₂O₄)₃] are respectively  

• 6 and +3

• 3 and 0

• 4 and +2

• 3 and +3

The equivalent weight of MnSO₄, is equal to its molecular weight when it is converted to

• Mn₂O₃

• MnO₂

• MnO${}_4^{-}$

• MnO${}_4^{2-}$

The mineral from which potassium permanganate is manufactured

• manganite, Mn₂O₃.H₂O

• pyrolusite, MnO₂

• Both (a) and (b)

• None of the above

The following compounds have identical molecular weight. Which would have the lowest boiling point?

• 2-butanol

• 2-methyl-1-propanol

• 1, 1-dimethyl ethanol

• 1-methoxypropane