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

Write the structures of main products when benzene diazonium chloride `(C_6H_5N_2^(+)Cl^-)`reacts with the following reagents:

CH₃CH₂OH

Give a reason for the following: 

Actinoids show irregularities in their electronic configurations.

Write the structures of A, B and C in the following:

Why pKa of F-CH₂-COOH is lower than that of Cl−CH₂−COOH?

What happens when the external pressure applied becomes more than the osmotic pressure of solution?

Blood cells are isotonic with 0.9% sodium chloride solution. What happens if we place blood cells in a solution containing

(i) 1.2% sodium chloride solution?

(ii) 0.4% sodium chloride solution?

How would you account for the following:

Actinoid contraction is greater than lanthanoid contraction.

Why do actinoids show a wide range of oxidation states?

Write on similarity between the chemistry of lanthanoids and actinoids.

Distinguish between the following : Benzoic acid and methyl benzoate

A solution containing 15 g urea (molar mass = 60 g mol^–1) per litre of solution in water has the same osmotic pressure (isotonic) as a solution of glucose (molar mass = 180 g mol^–1) in water. Calculate the mass of glucose present in one litre of its solution.

With reference to structural variability and chemical reactivity, write the differences between lanthanoids and actinoids

Give the structures of A, B and C in the following reaction:

Explain the following term with a suitable example:

F-centres

If NaCl is doped with 10⁻³ mol % of SrCl₂, what is the concentration of cation vacancies?

Calculate the osmotic pressure in pascals exerted by a solution prepared by dissolving 1.0 g of polymer of molar mass 185,000 in 450 mL of water at 37°C.

At 300 K, 36 g of glucose present in a litre of its solution has an osmotic pressure of 4.98 bar. If the osmotic pressure of the solution is 1.52 bars at the same temperature, what would be its concentration?

Determine the amount of CaCl₂ (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27°C.

Determine the osmotic pressure of a solution prepared by dissolving 25 mg of K₂SO₄ in 2 liter of water at 25°C, assuming that it is completely dissociated.

What is the difference between multimolecular and macromolecular colloids? Give one example of each. How are associated colloids different from these two types of colloids?