Based on the analysis of the provided "Alkanes Worksheet," here are the IUPAC names for each molecule from (a) to (j). The naming follows standard rules: identifying the longest continuous carbon chain, numbering it to give substituents the lowest possible numbers, and listing substituents in alphabetical order.
*
(a) 2-Methylbutane
* *Reasoning:* The longest chain is 4 carbons (butane). A methyl group is attached to carbon #2 when the chain is numbered to give the substituent the lowest number.
*
(b) 2,3-Dimethylbutane
* *Reasoning:* The longest chain is 4 carbons (butane). There are two methyl groups, one on carbon #2 and one on carbon #3.
*
(c) 3-Methylpentane
* *Reasoning:* The longest continuous chain is 5 carbons (pentane), which can be traced through the ethyl group. A methyl group is attached to carbon #3.
*
(d) 3-Methylheptane
* *Reasoning:* The longest continuous chain is 7 carbons (heptane), found by including the propyl substituent. A methyl group is attached to carbon #3.
*
(e) 3-Ethyl-4-methylheptane
* *Reasoning:* The longest chain is 7 carbons (heptane). An ethyl group is on carbon #3 and a methyl group is on carbon #4. Substituents are listed alphabetically (ethyl before methyl).
*
(f) 3-Methylhexane
* *Reasoning:* The longest chain is 6 carbons (hexane). A methyl group is attached to carbon #3.
*
(g) 2,2-Dimethylpropane
* *Reasoning:* The longest chain is 3 carbons (propane). Two methyl groups are attached to carbon #2.
*
(h) 3-Ethyl-2,2-dimethylpentane
* *Reasoning:* The longest chain is 5 carbons (pentane). An ethyl group is on carbon #3, and two methyl groups are on carbon #2. Substituents are listed alphabetically (ethyl before methyl).
*
(i) 2,2,4,4-Tetramethylhexane
* *Reasoning:* The longest chain is 6 carbons (hexane). There are four methyl groups: two on carbon #2 and two on carbon #4.
*
(j) 3-Ethyl-2,2,5-trimethylheptane
* *Reasoning:* The longest chain is 7 carbons (heptane). An ethyl group is on carbon #3, and three methyl groups are on carbons #2 and #5 (two on #2, one on #5). Substituents are listed alphabetically (ethyl before methyl).
Parent Tip: Review the logic above to help your child master the concept of alkanes worksheet.
