CBSE Class 10 Science 2022 · Paper 31/4/3 · Question 6

Carbon and its Compounds 2 marks Medium

Consider the carbon compounds having following molecular formula :

(i) $C_{2} H_{2}$
(ii) $C_{2} H_{6}$
(iii) $C_{3} H_{7} OH$
(iv) $C_{2} H_{5} COOH$
(v) $CH_{3} CHO$ (a) Identify which one of the above compounds, is a member of aldehyde series. (b) Write the general formula of the series to which compound $C_{2} H_{2}$ belongs. (c) Which one of the above compounds has triple bonds between carbon – carbon atoms ? (d) Write the molecular formula of the first member of the homologous series to which the compound $C_{3} H_{7} OH$ belongs.

Answer

Aldehyde: $CH_{3} CHO$ ; alkyne formula $C_{n} H_{2 n - 2}$ ; triple bond in $C_{2} H_{2}$ ; first alcohol is $CH_{3} OH$ .

(a) Compound (v),

CH_{3} CHO

(ethanal), which carries the aldehyde group

- CHO

. (b)

C_{2} H_{2}

is an alkyne; the general formula of the alkyne series is

C_{n} H_{2 n - 2}

. (c) Compound (i),

C_{2} H_{2}

(ethyne):

H - C \equiv C - H

. (d)

C_{3} H_{7} OH

is an alcohol; the first member of the alcohol series is methanol,

CH_{3} OH

(molecular formula

CH_{4} O

🔒 Step-by-step solution