Science (English Medium) Class 11 - CBSE Question Bank Solutions

Two liquids (A) and (B) can be separated by the method of fractional distillation. The boiling point of liquid (A) is less than boiling point of liquid (B). Which of the liquids do you expect to come out first in the distillate? Explain.

Draw a diagram of bubble plate type fractionating column. When do we require such type of a column for separating two liquids. Explain the principle involved in the separation of components of a mixture of liquids by using fractionating column. What industrial applications does this process have?

Arrange the following carbanions in order of their decreasing stability.

(A) H₃C – C ≡ C^–

(B) H – C ≡ C^–

(C) \[\ce{H3C - C\overset{-}{H2}}\]

Which of the following are correct?

(i) \[\ce{CH3 - O - CH^{⊕}2}\] is more stable than \[\ce{CH3 - CH^{⊕}2}\]

(ii) (CH₃)₂CH^⊕ is less stable than \[\ce{CH3 - CH2 - CH^{⊕}2}\]

(iii) \[\ce{CH3 = CH2 - CH^{⊕}2}\] is more stable than \[\ce{CH3 - CH2 - CH^{⊕}2}\]

(iv) \[\ce{CH2 - CH^{⊕}}\] is more stable than \[\ce{CH3 - CH^{⊕}2}\]

How will you convert benzene into p – nitrobromobenzene

How will you convert benzene into m – nitrobromobenzene

Arrange the following set of compounds in the order of their decreasing relative reactivity with an electrophile. Give reason.

The relative reactivity of 1°, 2°, 3° hydrogen’s towards chlorination is 1 : 3.8 : 5. Calculate the percentages of all monochlorinated products obtained from 2-methylbutane.

The bromine atom possesses 35 electrons. It contains 6 electrons in 2p orbital, 6 electrons in 3p orbital and 5 electrons in 4p orbital. Which of these electron experiences the lowest effective nuclear charge?

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge?

1. 2s and 3s,
2. 4d and 4f,
3. 3d and 3p

A reaction, A + B → C + D + q is found to have a positive entropy change. The reaction will be ______.

For the reaction, \[\ce{2Cl_{(g)} → Cl_{2(g)}}\], what are the signs of ΔH and ΔS?

What are the necessary conditions for any system to be aromatic?

Explain why the following system is not aromatic?

Explain why the following system is not aromatic?

Explain why the following system is not aromatic?

The ionization constant of propanoic acid is 1.32 × 10^–5. Calculate the degree of ionization of the acid in its 0.05M solution and also its pH. What will be its degree of ionization if the solution is 0.01M in HCl also?

One mole of any substance contains 6.022 × 10²³ atoms/molecules. Number of molecules of \[\ce{H2SO4}\] present in 100 mL of 0.02 M \[\ce{H2SO4}\] solution is ______.

Which of the following statements about a compound is incorrect?

16 g of oxygen has same number of molecules as in:

(i) \[\ce{16 g of CO}\]

(ii) \[\ce{28 g of N2}\]

(iii) \[\ce{14 g of N2}\]

(iv) \[\ce{1.0 g of H2}\]