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

On adding NaOH to ammonium sulphate, a colourless gas with pungent odour is evolved, which forms a blue-coloured complex with Cu²⁺ ion. Identify the gas.

Out of 1 M glucose and 2 M glucose, which one has a higher boiling point and why?

Name the reagents used in the following reactions:

Why is elevation of boiling point a colligative property?

Define the following term: 

Molal elevation constant (K_b)

Based on molecular forces, what type of polymer is neoprene?

Explain the following term with suitable examples: 

Frenkel defect

Explain the following term with a suitable example:

Interstitials

Boiling point of water at 750 mm Hg is 99.63°C. How much sucrose is to be added to 500 g of water such that it boils at 100°C? Molal elevation constant for water is 0.52 K kg mol⁻¹.

Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.

Explain the term with suitable examples:

Alcosol

Explain the term with suitable examples:

Aerosol

Explain the term with suitable examples:

Hydrosol

Aqueous copper sulphate solution (blue in colour) gives a green precipitate with aqueous potassium fluoride. Explain this experimental result.

A solution of [Ni(H₂O)₆]²⁺ is green but a solution of [Ni(CN)₄]²⁻ is colourless. Explain.

[Fe(CN)₆]⁴⁻ and [Fe(H₂O)₆]²⁺ are of different colours in dilute solutions. Why?

What will be the correct order for the wavelengths of absorption in the visible region for the following?

[Ni(NO₂)₆]⁴⁻, [Ni(NH₃)₆]²⁺, [Ni(H₂O)₆]²⁺

Define the following as related to proteins:

Peptide linkage

What are the common types of secondary structure of proteins?

What type of bonding helps in stabilising the α-helix structure of proteins?