Biomolecules — Chemistry STD 12 Science — Question

1. How are lipids classified? Give an example of each class.
2. Explain the following terms:

1. Mutarotation.
2. Avitaminosis.

CoSO₄Cl.5NH₃ exists in two isomeric forms ‘A’ and ‘B’. Isomer ‘A’ reacts with AgNO₃ to give white precipitate, but does not react with BaCl₂. Isomer ‘B’ gives white precipitate with BaCl₂ but does not react with AgNO₃. Answer the following questions.

1. Identify ‘A’ and ‘B’ and write their structural formulas.
2. Name the type of isomerism involved.
3. Give the IUPAC name of ‘A’ and ‘B’.

1. Account for the following:

1. Transition metals show variable oxidation states.
2. Zn, Cd and Hg are soft metals.
3. E^o value for the Mn³⁺/Mn²⁺ couple is highly

positive (+ 1·57 V) as compared to Cr³⁺/Cr²⁺.

2. Write one similarity and one difference between the chemistry of lanthanoid and actinoid elements.

With the help of an example explain what is meant by pseudo first order reaction.

An organic compound A with molecular formula C₇H₇NO reacts with Br₂/aq. KOH to give compound B, which upon reaction with NaNO₂ and HCl at 0°C gives C. Compound C on heating with CH₃CH₂OH gives a hydrocarbon D. Compound B on further reaction with Br₂ water gives white precipitate of compound E. Identify the compound A, B, C, D and E; also justify your answer by giving relevant chemical equations.

(i). Illustrate the following reactions giving suitable example in each case:
a. Ammonolysis
b. Coupling reaction
c. Acetylation of amines
(ii). Describe Hinsberg method for the identification of primary, secondary and tertiary amines. Also, write the chemical equations of the reactions involved.

What are co-ordination compounds ? Mention the differences between complex compounds and double salts.

Answer the following questions:
Is the variability in oxidation number of transition elements different from that of non–transition elements? Illustrate with examples.

What is abnormal molar mass? Explain.