Science (English Medium) इयत्ता १२ - CBSE Question Bank Solutions

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⁺

How do you explain the amphoteric behaviour of amino acids?

Describe a method for the identification of primary, secondary and tertiary amines. Also write chemical equations of the reactions involved.

Give a plausible explanation for the following:

Why do primary amines have higher boiling points than tertiary amines?

Predict the product of the following reaction:

\[\ce{CH3 - CH2 - CH2 - O - CH3 + HBr ->}\]

Predict the product of the following reaction:

Predict the product of the following reaction:

\[\ce{(CH3)3C - OC2H5 ->[HI]}\]

Show how will you synthesize cyclohexylmethanol using an alkyl halide by an S_N2 reaction.

Write the equation of the reaction of hydrogen iodide with 1-propoxypropane.

Write the equation of the reaction of hydrogen iodide with methoxybenzene.

Write the equation of the reaction of hydrogen iodide with benzyl ethyl ether.

Explain the fact that in aryl alkyl ethers 

1. the alkoxy group activates the benzene ring towards electrophilic substitution and
2. it directs the incoming substituents to ortho and para positions in the benzene ring.

Write the mechanism of the reaction of HI with methoxymethane.

Give the uses of freon 12.

How the following conversion can be carried out?

Isopropyl alcohol to iodoform

How the following conversion can be carried out?

Aniline to phenylisocyanide

Write the structures of the monomers used for getting the following polymers

Melamine – formaldehyde polymer

Write one difference between Multimolecular colloid and Macromolecular colloid

Write one difference between Sol and Gel

Write one difference between O/W emulsion and W/O emulsion