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

An electron is in one of the 3d orbitals. Give the possible values of n, l and m_l for this electron.

The unpaired electrons in Al and Si are present in 3p orbital. Which electrons will experience more effective nuclear charge from the nucleus?

What is meant by hybridisation of atomic orbitals?

Describe the shapes of sp, sp²,sp³ hybrid orbitals.

Describe the change in hybridisation (if any) of the Al atom in the following reaction.

\[\ce{AlCl_3 + Cl- -> AlCl_4-}\]

Is there any change in the hybridisation of B and N atoms as a result of the following reaction?

\[\ce{BF3 + NH3 → F3B.NH3}\]

Considering x-axis as the internuclear axis which out of the following will not form a sigma bond and why?

1. 1s and 1s
2. 1s and 2px
3. 2py and 2py
4. 1s and 2s.

Which hybrid orbitals are used by carbon atoms in the following molecules?

CH₃–CH₃

For the reaction at 298 K,

\[\ce{2A + B → C}\]

ΔH = 400 kJ mol^-1 and ΔS = 0.2 kJ K^-1 mol^-1

At what temperature will the reaction become spontaneous considering ΔH and ΔS to be constant over the temperature range?

For the reaction

\[\ce{2A_{(g)} + B_{(g)} → 2D_{(g)}}\]

ΔU^θ = –10.5 kJ and ΔS^θ= –44.1 JK^–1.

Calculate ΔG^θ for the reaction, and predict whether the reaction may occur spontaneously.

Why is benzene extra ordinarily stable though it contains three double bonds?

Write down the products of ozonolysis of 1, 2-dimethylbenzene (o-xylene). How does the result support Kekulé structure for benzene?

Give a brief description of the principle of the following technique taking an example.

Distillation 

What is the difference between distillation, distillation under reduced pressure and steam distillation ?

What will be the conjugate bases for the following Bronsted acids:

HF, H₂SO₄ and \[\ce{HCO^-_3}\]? 

Which hybrid orbitals are used by carbon atoms in the following molecules?

CH₃–CH=CH₂

Which hybrid orbitals are used by carbon atoms in the following molecules?

CH₃-CH₂-OH

Which hybrid orbitals are used by carbon atoms in the following molecules?

CH₃-CHO

Which hybrid orbitals are used by carbon atoms in the following molecules?

CH₃COOH

What will be the molarity of a solution, which contains 5.85 g of NaCl(s) per 500 mL?