Class 10 Carbon and its Compound



Q-10: Which of the following is the correct representation of the electron dot structure of nitrogen?

Therefore, it needs three more electrons to complete its octet. Each nitrogen atom shares there electrons to form a molecule of  as

Q-11: Structural formula of ethyne is

General formula of alkyne is CnH2n-2

Solution:(a) Earth showed the pressure of two carbon atoms and ‘any’ shows the presence of triple bonds. Thus, ethyne has the structure,

Q-12: Identify the unsaturated compound from the following.


A hydrocarbon in which the two carbon atoms are connected by a ‘double bound’ or triple bound’ is called an unsaturated hydrocarbon.

both have double and triple bond, respectively hence unsaturated. Propane and chloropropane are saturated hydrocarbons which contain only single bonds.

Q-13:Chlorine reacts with saturated hydrocarbons at room temperature in the

(a) absence of sunlight                               (b) presence of sunlight

(c) presence of water                           (d) presence of hydrochloric acid


Chlorine reacts with saturated hydrocarbon at room temperature in the presence of sunlight.

Q-14:In the soap micelles

(a) the ionic end of the soap is on the surface of the cluster while the carbon chain is in the interior of the cluster

(b) ions end of soap is in the interior of the cluster and the carbon chain is out of the cluster

(c) Bothe ionic end carbon are in the interior of the cluster

(d) both ionic end and carbon chain are on the exterior of the cluster

Solution: (a) A ‘spherical aggregate of soap molecules’ in the soap solution in water is called a ‘micelle’. In a soap micelle, the molecules are arranged readily with hydrocarbon ends directed towards the centre and ionic ends directed outwards

Q-15:Pentane has the molecular formula C5H12 It has

(a) 5 covalent bonds                              (b) 12 covalent bonds

(c) 16 covalent bonds                             (d) 17 covalent bonds


The structural formula of pentane is C5H12

It contains 16 covalent bonds.

Q-16:Structural formula of benzene is






Benzene molecule contains alternate single and double bonds. Its formula is C6H6 in structure (b) formula is C6H8

In structure (c) double bonds is not at alternate. In (d) formula is C6H12therefore, option (c) is correct.

Q-17: Ethanol reacts with sodium and forms two products. These are

(a) sodium ethanoate and hydrogen

(b) sodium ethanoate and oxygen

(c) sodium ethoxide and hydrogen

(d) sodium ethoxide and oxygen


Ethanol reacts with sodium to form sodium ethoxide and hydrogen gas.