A gas is allowed to expand in a well-insulated container against a constant external pressure of 2.5atm from an initial volume of 2.50 L to a final volume of 4.50L. The change in internal energy U of the gas in joules will be:
1. –500J
2. –505J
3. –506J
4. –508J

Mark the correct reaction among the following to convert acetamide to methenamine:

1. Hoffmann bromamide reaction

2. Stephens reaction

3. Gabriels phthalimide synthesis

4. Carbylamine reaction

With respect to the conformers of ethane, which of the following statements is true?

In which pair of ions both the species contain S-S bond?

1. ${\mathrm{S}}_2{\mathrm{O}}_7^{2-},$ ${\mathrm{S}}_2{\mathrm{O}}_8^{2-}$

2. ${\mathrm{S}}_4{\mathrm{O}}_6^{2-},$ ${\mathrm{S}}_2{\mathrm{O}}_3^{2-}$

3. ${\mathrm{S}}_4{\mathrm{O}}_6^{2-},$ ${\mathrm{S}}_2{\mathrm{O}}_7^{2-}$

4. ${\mathrm{S}}_2{\mathrm{O}}_7^{2-},$ ${\mathrm{S}}_2{\mathrm{O}}_3^{2-}$

The correct statement among the following is :

The correct increasing order for the wavelengths of absorption in complexes of Co³⁺ is:

1. [Co(H₂O)₆]³⁺ < [Co(en)₃]³⁺ < [Co(NH₃)₆]^{3 +}

2. [Co(H₂O)₆]³⁺ <  [Co(NH₃)₆]³⁺ <  [Co(en)₃]³⁺

3. [Co(NH₃)₆]³⁺ < [Co(en)₃]³⁺ < [Co(H₂O)₆]³⁺

4. [Co(en)₃]³⁺ <  [Co(NH₃)₆]³⁺ < [Co(H₂O)₆]³⁺

A, X, Y, and Z in the above-mentioned reaction are:
 

Which product is generated when cyclohexanone undergoes
aldol condensation and is subsequently heated?

1.		2.
3.		4.

Which of the following pairs of species have the same bond order?

1. $O_2^{-},N{O}^{+}$

2. $C{N}^{-},CO$

3. $N_2, O_2^{-}$

2. CO, NO

Extraction of gold and silver involves leaching with CN^- ion. Silver is later recovered by:

1. Distillation

2. Zone refining

3. Displacement with Zn

4. Liquation