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

Convert the following into basic units:

25365 mg

In terms of period and group, where would you locate the element with Z =114?

Which element do you think would have been named by Lawrence Berkeley Laboratory?

Which element do you think would have been named by Seaborg’s group?

Write Lewis dot symbols for atoms of the following elements: Mg, Na, B, O, N, Br.

Draw the Lewis structures for the following molecule and ion:

H₂S

Draw the Lewis structures for the given molecule and ion:

SiCl₄

Draw the Lewis structures for the given molecule and ion:

BeF₂

Draw the Lewis structures for the given molecule and ion:

`"CO"_3^(2-)`

Draw the Lewis structures for the following molecule and ion:

HCOOH

Explain why BeH₂ molecule has a zero dipole moment although the Be–H bonds are polar.

What are the reactions involved for ozone layer depletion in the stratosphere?

Is boric acid a protic acid? Explain.

Explain what happens when boric acid is heated.

Explain the Structure of Boric Acid.

Explain the following reaction.

Hydrated alumina is treated with aqueous NaOH solution.

A certain salt X, gives the following results.

1. Its aqueous solution is alkaline to litmus.
2. It swells up to a glassy material Y on strong heating.
3. When conc. H₂SO₄ is added to a hot solution of X, white crystal of an acid Z separates out.

Write equations for all the above reactions and identify X, Y and Z.

Write a balanced equation for B₂H₆ + H₂O → ?

Write a balanced equation for NaH + B₂H₆ → ?