Science (English Medium) Class 12 - CBSE Question Bank Solutions for Chemistry

State the role of silica in the metallurgy of copper.

The choice of a reducing agent in a particular case depends on thermodynamic factor. How far do you agree with this statement? Support your opinion with two examples.

Explain on the basis of valence bond theory that [Ni(CN)₄]²⁻ ion with square planar structure is diamagnetic and the [NiCl₄]²⁻ ion with tetrahedral geometry is paramagnetic.

Predict the number of unpaired electrons in the square planar [Pt(CN)₄]²⁻ ion.

Discuss the nature of bonding in the following coordination entity on the basis of valence bond theory:

[Fe(CN)₆]⁴⁻

[Cr(NH₃)₆]³⁺ is paramagnetic while [Ni(CN)₄]²⁻ is diamagnetic. Explain why?

Discuss the nature of bonding in the following coordination entity on the basis of valence bond theory:

[FeF₆]³⁻

Discuss the nature of bonding in the following coordination entity on the basis of valence bond theory:

[Co(C₂O₄)₃]³⁻

Discuss the nature of bonding in the following coordination entity on the basis of valence bond theory:

[CoF₆]³⁻

Why do we require artificial sweetening agents?

What are food preservatives?

Why is use of aspartame limited to cold foods and drinks?

What are artificial sweetening agents? Give two examples.

Name a sweetening agent used in the preparation of sweets for a diabetic patient.

What problem arises in using alitame as artificial sweetener?

Complete the following reaction:

\[\ce{C6H5NH2 + CHCl3 + alc. KOH ->}\]

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