Draw the line-angle formula for the following condensed structural formulas

Draw the line-angle formula for the following condensed structural formulas.

a. CH3(CH2)3CH(CH3)2

b. CH3CH2COCN

c. (CH3)3CCOCHCH2

d. (CH3CH2)2CO

e. (CH3)2CHCH2Cl

The correct answer and explanation is :

Sure! I’ll draw and explain the line-angle structures for each given condensed formula and provide a detailed explanation of how to interpret and convert them.

a. CH3(CH2)3CH(CH3)2

Step 1: Expand the formula.

• CH3- (methyl group)
• (CH2)3 – three methylene (-CH2-) groups in a chain
• CH(CH3)2 – a carbon attached to two methyl groups (an isopropyl group)

So the full structure is:
CH3 – CH2 – CH2 – CH2 – CH(CH3)2

This is 2,2-dimethylpentane (a pentane backbone with two methyl groups on the second carbon).

Line-angle formula:
Draw a straight chain of 5 carbons, with the second carbon bearing two short branches (lines) representing the two methyl groups.

b. CH3CH2COCN

Let’s break it down:

• CH3CH2- is an ethyl group
• CO is carbonyl group (=O)
• CN is a nitrile group (-C≡N)

This is ethyl cyanate or ethyl isocyanate, but looking carefully, it’s likely ethyl cyanate (ethyl isocyanate), but since CO is followed by CN, it’s likely an acyl cyanide:

The structure is: CH3CH2-C(=O)-C≡N

Line-angle formula:
A chain of two carbons (ethyl) attached to a carbonyl carbon, which is then attached to a nitrile group.

c. (CH3)3CCOCHCH2

Breakdown:

• (CH3)3C- is a tert-butyl group (a carbon bonded to three methyl groups)
• CO is carbonyl (=O)
• CHCH2 indicates a vinyl group attached to the carbonyl carbon (like an α,β-unsaturated ketone)

Full structure:
tert-butyl attached to carbonyl (ketone), then attached to vinyl group

This is tert-butyl vinyl ketone.

Line-angle formula:
A tert-butyl group connected to a carbonyl carbon, which is double-bonded to oxygen and single bonded to a vinyl group.

d. (CH3CH2)2CO

Breakdown:

• (CH3CH2)2 means two ethyl groups
• CO is carbonyl

This is diethyl ketone or 3-pentanone (a ketone with ethyl groups on either side of the carbonyl).

Line-angle formula:
Five carbon chain with a ketone on the middle carbon (carbon 3). Or equivalently, a carbonyl carbon bonded to two ethyl groups.

e. (CH3)2CHCH2Cl

Breakdown:

• (CH3)2CH- is isopropyl group (carbon with two methyl groups)
• CH2Cl is chloromethyl group

Full structure: isobutyl chloride

Line-angle formula:
A chain with three carbons (with a branching at second carbon) and a chlorine attached to the terminal carbon.

Line-Angle Formulas (Sketch descriptions):

Detailed Explanation (300 words):

Line-angle formulas (also called skeletal formulas) are simplified chemical structure drawings where carbon atoms are implied at the ends and intersections of lines, and hydrogen atoms bonded to carbons are omitted for clarity. Each vertex represents a carbon atom, and lines represent covalent bonds.

How to convert condensed formulas:

1. Identify the carbon chain:
   Look for repeating units or parentheses indicating branching. For example, in CH3(CH2)3CH(CH3)2, the main chain is 5 carbons long, with branching on the 4th carbon.
2. Recognize branches and substituents:
   Parentheses indicate groups attached to the main chain. In CH(CH3)2, the central carbon is bonded to two methyl groups. This should be drawn as branches from that carbon.
3. Identify functional groups:
   Groups like CO (carbonyl) and CN (nitrile) indicate double bonds to oxygen or triple bonds to nitrogen. For example, CH3CH2COCN has a ketone (carbonyl) attached to a nitrile group.
4. Draw the carbon backbone first:
   Sketch the longest continuous chain or the core structure, then add branches and functional groups.
5. Apply line-angle conventions:
   • Vertices and ends of lines are carbons.
   • Hydrogens are not drawn unless bonded to heteroatoms (like Cl).
   • Heteroatoms like O, N, Cl are drawn explicitly.

Examples from the given:

• Compound a (2,2-dimethylpentane) shows a pentane backbone with two methyl groups on the second carbon, so the line-angle structure is a zigzag with two branches at the second vertex.
• Compound b (ethyl ketone with nitrile) includes functional groups; draw the chain, then the carbonyl and nitrile groups.
• Compound c (tert-butyl vinyl ketone) includes a bulky tert-butyl group (three methyl groups attached to one carbon) attached to a ketone, and then a vinyl group attached to the ketone carbon.
• Compound d (diethyl ketone) is symmetric with two ethyl groups on either side of the ketone.
• Compound e (isobutyl chloride) has a chlorine substituent on the terminal carbon of an isobutyl group.