Class 10 Science - Chapter Carbon and Its Compound NCERT Solutions | Explain the nature of the covalent bond

Draw the structure for the following compounds.                

       (i)    Ethanoic acid             (ii)   Bromopentane*
       (iii)  Butanone                   (iv)   Hexanal.

*Are structural isomers possible for bromopentane?

What is an homologous series? Explain with an example.

How would you name the following compounds?

   (i)    CH₃  -- CH₂  -- Br

  (ii)

(iii) 

What will be the formula and electron dot structure of cyclopentane?

Why are carbon and its compounds used as fuels for most applications?

How many structural isomers can you draw for pentane?

Explain the mechanism of the cleaning action of soaps.

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?

Explain the formation of scum when hard water is treated with soap.

How would you distinguish experimentally between an alcohol and a carboxylic acid?

Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.

What is a good source of energy?

Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?

What are trophic levels? Give an example of a food chain and state the different trophic levels in it.

What changes can you make in your habits to become more environment-friendly?

What is the difference between a reflex action and walking?

What is the importance of DNA copying in reproduction?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Why should a magnesium ribbon be cleared before burning in air?

Define the principal focus of a concave mirror.

Outline a project which aims to find the dominant coat colour in dogs.

Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?

On what basis would you classify energy sources as

(a) renewable and non-renewable?
(b) exhaustible and inexhaustible?

Are the options given in (a) and (b) the same?

Which of the following methods is suitable for preventing an iron frying pan from rusting?

(a) Applying grease
(b) Applying paint
(c) Applying a coating of zinc
(d) All of the above.

Name some sources of direct current.

How does our body respond when adrenaline is secreted into the blood?

Why do we prefer a convex mirror as a rear-view mirror in vehicles?

How are the lungs designed in human beings to maximise the area for exchange of gases?

An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp focussed image can be obtained? Find the size and the nature of the image.

In the Modern Periodic Table, calcium (atomic number 20) is surrounded by elements with atomic numbers 12, 19, 21 and 38. Which of these have physical and chemical properties resembling calcium?