For question numbers 1 and 2, two statements are given - one labelled Answer to these questions from the codes (i), (ii), (ub and (iv) as given
Both (A) and (R) are true and (R) is correct explanation of the
assertion (A).
(ii)
Both (A) and (R) are true, but (R) is not the correct explanation of
the assertion (A).
(iii)
(A) is true, but (R) is false.
(iv) (A) is false, but (R) is true.
Assertion (A) : Carbon has a strong tendency to either lose or gain
electrons to attain noble gas configuration.
Reason (R):
Carbon has four electrons in its outermost shell and has
the tendency to share electrons with carbon or other
elements.
Assertion (A) and the other labelled Reason (R). Select the correct

(iv) (A) is false, but (R) is true.

Explanation:

It is not true that carbon has a strong tendency to either lose or gain electrons to attain noble gas configuration. Carbon is a member of group 14, it is the first member of the group and carbon is purely a non metal. Only metals metals can loose electrons to attain the noble gas configuration. Moreover, carbon does not participate in ionic bonding so it does not gain electrons to attain the noble gas configuration.

However, carbon participates in covalent bonding where it is covalently bonded to four other chemical species using its four outermost electrons. Carbon forms covalent bonds in which four electrons are shared with other chemical species.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.