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

How many significant figures should be present in the answer of the following calculation?

0.0125 + 0.7864 + 0.0215

Write the general outer electronic configuration of p- block elements.

In Rutherford’s experiment, generally the thin foil of heavy atoms, like gold, platinum etc. have been used to be bombarded by the α-particles. If the thin foil of light atoms like aluminium etc. is used, what difference would be observed from the above results?

Write the favourable factors for the formation of the ionic bond.

How do you account for the formation of ethane during chlorination of methane?

Why does boron trifluoride behave as a Lewis acid?

Consider the compound, CCl₄. How will CCl₄ behave with water? Justify.

Describe the shapes of BF₃ and BH₄^–. Assign the hybridisation of boron in these species.

What is allotropy?

What do you understand by catenation?

Write a balanced equation for  BF₃ + LiH → ?

Draw the structure of BeCl₂ (vapour).

Draw the structure of BeCl₂ (solid).

Classify the following reaction in one of the reaction type studied in this unit.

\[\ce{CH3CH2Br + HS– → CH3CH2SH + Br–}\]

Classify the following reaction in one of the reaction type studied in this unit.

\[\ce{(CH3)2 C = CH2 + HCl → (CH3)2 ClC–CH3}\]

Classify the following reaction in one of the reaction type studied in this unit.

\[\ce{CH3CH2Br + HO– → CH2 = CH2 + H2O + Br–}\]

Classify the following reaction in one of the reaction type studied in this unit.

\[\ce{(CH3)3 C – CH2 OH + HBr → (CH3)2 CBrCH2CH3 + H2O}\]

What do you understand by the term “non-stoichiometric hydrides”? Do you expect this type of the hydrides to be formed by alkali metals? Justify your answer.

How do you expect the metallic hydrides to be useful for hydrogen storage? Explain.

Justify giving reactions that among halogens, fluorine is the best oxidant and among hydrohalic compounds, hydroiodic acid is the best reductant.