Science (English Medium) कक्षा १२ - CBSE Question Bank Solutions for Chemistry

Write the equation of the following reaction:

Bromination of anisole in an ethanoic acid medium.

Write the equation of the following reaction:

Friedel-Craft’s acetylation of anisole.

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

Write the reactions involved Hell-Volhard Zelinsky reaction?

What type of colloid is formed when a gas is dispersed in a liquid? Give an example

Using IUPAC norms write the formulae for Potassium trioxalatoaluminate(III)

Using IUPAC norms write the formulae for Dichloridobis(ethane-1,2-diamine)cobalt(III)

Write the structures of the main products in the following reactions :

Give reasons Dioxygen is a gas while Sulphur is a solid at room temperature.

Calculate the mass of NaCl (molar mass = 58.5 g mol⁻¹) to be dissolved in 37.2 g of water to lower the freezing point by 2°C, assuming that NaCl undergoes complete dissociation. (K_f for water = 1.86 K kg mol⁻¹)

How would you account the following :

Highest fluoride of Mn is MnF₄ whereas the highest oxide is Mn₂O₇.

Calculate the mass of a compound (molar mass = 256 g mol⁻¹) to be dissolved in 75 g of benzene to lower its freezing point by 0.48 K (K_f = 5.12 K kg mol⁻¹).

Write an important characteristic of lyophilic sols.

How do you prepare:

Na₂Cr₂O₇ from Na₂CrO₄?

How do you prepare:

Actinoid elements show wide range of oxidation states.

Account for the following:

Carboxylic acid is a stronger acid than phenol.

What happens when Salicylic acid is treated with (CH₃CO)₂ O/H⁺?

What happens when Anisole is treated with CH₃Cl/anhydrous  AlCl₃?

 Arrange the following compounds in increasing order of their property as indicated:
 F - CH₂COOH, O₂N - CH₂ COOH CH₃ COOH,HCOOH - acid character. 

Why phenol undergoes electrophilic substitution more easily than benzene?