PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions for Chemistry

[Fe(H₂O)₆]³⁺ is strongly paramagnetic whereas [Fe(CN)₆]³⁻ is weakly paramagnetic. Explain.

Explain [Co(NH₃)₆]³⁺ is an inner orbital complex, whereas [Ni(NH₃)₆]²⁺ is an outer orbital complex.

[At. No.: Co = 27, Ni = 28]

Amongst the following ions, which one has the highest magnetic moment value?

What are the monomeric repeating units of Nylon-6 and Nylon-6, 6?

What is a biodegradable polymer? Give an example of a biodegradable aliphatic polyester.

Account for the following:

Although the amino group is o, p-directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m-nitroaniline.

Write short notes on acetylation.

What is meant by the following term? Give an example of the reaction in the following case.

Aldol

Which of the following compounds would undergo aldol condensation, which the Cannizzaro reaction and which neither? Write the structures of the expected products of aldol condensation and Cannizzaro reaction.

1. Methanal
2. 2-Methylpentanal
3. Benzaldehyde
4. Benzophenone
5. Cyclohexanone
6. 1-Phenylpropanone
7. Phenylacetaldehyde
8. Butan-1-ol
9. 2, 2-Dimethylbutanal

How will you convert ethanal into the following compound?

Butane-1, 3-diol

How will you convert ethanal into the following compound?

But-2-enal

Write structural formulas and names of four possible aldol condensation products from propanal and butanal. In each case, indicate which aldehyde acts as nucleophile and which as electrophile.

How will you bring about the following conversion in not more than two steps?

Ethanol to 3-Hydroxybutanal

How will you bring about the following conversion in not more than two steps?

Benzaldehyde to 3-Phenylpropan-1-ol

Describe the following:

Cross aldol condensation

Complete the synthesis by giving missing starting material, reagent or product.

\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]

Write the reactions of Williamson synthesis of 2-ethoxy-3-methylpentane starting from ethanol and 3-methylpentan-2-ol.

Which of the following is an appropriate set of reactants for the preparation of 1-methoxy-4-nitrobenzene and why?

(i)	(ii)

Write the name of the reagent and the equation for the preparation of the following ether by Williamson’s synthesis:

1-Propoxypropane