Ncert Solutions Chemistry Class 11th

13.26. Assertion: Out of staggered and the eclipsed conformations of ethane, staggered conformation is more stable. 

Reason: Hydrogen atoms are farthest apart in staggered conformation.

13.20. How would you convert the following compounds into benzene?
(i) Ethyne (ii) Ethene (iii) Hexane.

13.4. Write IUPAC names of the products obtained by the ozonolysis of the following compounds:
(i) Pent-2-ene (ii) 3, 4-Dimethylhept-3-ene (iii) 2-Ethylbut-l-ene (iv) 1-Phenylbut-l-ene.

14.3. Ozone depletion is mainly due to

14.2. BOD is a measure of

14.1. Which acid is most abundant in acid rain?

14.5 Assertion: It is important to maintain the ozone shield ozone (O₃).

Reason: O₃ protects us from the harmful ultraviolet (UV) radiations coming from the sun.

14.5 Assertion: It is important to maintain the ozone shield ozone (O₃).

Reason: O₃ protects us from the harmful ultraviolet (UV) radiations coming from the sun.

14.4 Assertion: As insect resistance of DDT increased, other organic toxins such as Aldrin and Dieldrin were introduced in the market by pesticide industry.

Reason: The repeated use of the same or similar pesticides give rise to pests that are resistant to that group of pesticides thus making the pesticides ineffective.

14.1 Assertion: Atmosphere trapping the sun's heat near the earth's surface is called natural greenhouse effect.

Reason: Atmosphere trapping the sun's heat maintains the temperature and makes the earth perfect for life.