Hardening of oil is done by

• dehydrogenation

• hydrogenation

• dehydrohalogenation

• dehydration

Copper is a divalent metal. The value of its electrochemical equivalent is 3.29 × 10^-4 g. Its atomic mass is

• 31.74 g

• 63.5 g

• 126.9 g

• 15.87 g

In ...... process, work is done at the expense of internal energy.

• isothermal

• isochoric

• adiabatic

• isobaric

The standard reduction potential for Mg²⁺ /Mg is - 2.37 V and for Cu²⁺ /Cu is 0.337. The E${}_{\mathrm{cell}}^{°}$ for the following reaction is

Mg + Cu²⁺ → Mg²⁺ + Cu

• +2.03 V

• -2.03 V

• -2.7 V

• +2.7 V

Which is a correct integrated rate equation?

• $\mathrm{k} = -\frac{2.303}{\mathrm{t}} \log \frac{\mathrm{a}}{\mathrm{a} - \mathrm{x}}$

• $\mathrm{k} = \frac{-2.303}{\mathrm{t}} \log \frac{\mathrm{a} - \mathrm{x}}{\mathrm{a}}$

• - d (a - x) = kdt

• All are integrated rate equations

For which order reaction, the unit of rate constant is time^-1?

• Zero order

• First order

• Second order

• Third order

The number of electrons required to reduce 4.5 × 10^-5 of Al is

• 1.03 × 10¹⁸

• 3.01 × 10¹⁸

• 4.95 × 10²⁶

• 7.31 × 10²⁰

28.

Maximum depression in freezing point is caused by

• potassium chloride

• sodium sulphate

• magnesium sulphate

• magnesium carbonate

Which of the following is not a colligative property?

• Elevation in boiling point

• Lowering of vapour pressure

• Osmotic pressure

• Freezing point

Most basic hydroxide among the following is

• Lu(OH)₃

• Eu(OH)₃

• Yb(OH)₃

• Ce(OH)₃