Answer
a) The given name is incorrect. The correct name is 2-methylbutane.
b) The given name is incorrect. The correct name is 3-iodo-3-methylheptane
c) The given name is incorrect. The correct name is 2-methyl-2-pentene.
d) The given name is incorrect. The correct name is 3-bromo-2-butanol.
Work Step by Step
a) If we draw the structure of the compound according to the given name we see that there are 4 C in the longest straight chain. So, the word root is 'but'. and one methyl group is present as a substituent at C2 position. So, the correct name will be 2-methylbutane.
b) If we draw the structure of the compound according to the given name we see that there are 7 C in the straight chain. So, the word root is 'hept'. one iodo group and one methyl group are present at C3 position. So, 3-iodo-3-mehyl is added before 'hept' and ending name will be 'ane'.
c) If we draw the structure of the compound according to the given name we see that the position of the double bond is at C2 position and not at C3 position (numbering should be done so that the double bond gets minimum number). Also, one methyl group is present as a substituent at C2 position. So, the name is 2-methyl-2-pentene. and cis trans isomerism is not possible due to two same groups are present at one of the double bonded Carbons (C2 Carbon).
d) If we draw the structure of the compound according to the given name we see that the position of the OH is at C2 position rather than C3 position. It is because it will get the preference over Br as OH is the main functional group. So, the position of the Br is at C3 position and the correct name will be 3-bromo-2-butanol.
