Question

3a. explain the ff. terms: (i) primary alcohol (ii) secondary // (iii) tertiary // b. give an example in each case c. consider the ff. fcas list of compounds (i) c(ch3)ch (ii) ch3c≡cch3 ch3cooch3 ch3ch(oh)cooh from the list above, choose one compound which (i) could readily decolorize br2ccl4 (ii) is an isomer of butane

Explanation:

• (i) Primary alcohol: An alcohol where the -OH group is attached to a carbon atom that is bonded to only one other carbon atom. Example: Ethanol ($CH_3CH_2OH$).
• (ii) Secondary alcohol: An alcohol where the -OH group is attached to a carbon atom that is bonded to two other carbon atoms. Example: 2 - Propanol ($CH_3CH(OH)CH_3$).
• (iii) Tertiary alcohol: An alcohol where the -OH group is attached to a carbon atom that is bonded to three other carbon atoms. Example: 2 - Methyl - 2 - propanol ($(CH_3)_3COH$).
• (c)(i): Compounds that can decolorize $Br_2/CCl_4$ are unsaturated compounds. Among the given compounds, $CH_3C\equiv CCH_3$ (an alkyne) can do this as it has a triple - bond and can undergo addition reactions with bromine.
• (c)(ii): An isomer of butane has the same molecular formula ($C_4H_{10}$) as butane. The compound $(CH_3)_3CH$ (2 - Methyl - propane) is an isomer of butane.

Answer:

• (i) An alcohol with -OH on a carbon bonded to one other carbon; Ethanol.
• (ii) An alcohol with -OH on a carbon bonded to two other carbons; 2 - Propanol.
• (iii) An alcohol with -OH on a carbon bonded to three other carbons; 2 - Methyl - 2 - propanol.
• (c)(i) $CH_3C\equiv CCH_3$
• (c)(ii) $(CH_3)_3CH$