Draw a Lewis structure for each of the compounds below

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2.1 Draw a Lewis structure for each of the compounds below:
(a) CH2=CHOCH2CH(CH3)2
(b) (CH3CH2)2CHCH2CH2OH
(c) (CH3CH2)3COH
(d) (CH3)2C=CHCH2CH3
(e) CH2=CHCH2OCH2CH(CH3)2
(f) (CH3CH2)2C=CH2
(g) (CH3)3CCH2CH2OH
(h) CH3CH2CH2CH2CH2CH3
(i) CH3CH2CH2OCH3
(j) (CH3CH2CH2)2CHOH
(k) (CH3CH2)2CHCH2OCH3
(1) (CH3)2CHCH2OH
2.2 Identify which two compounds below are constitutional isomers:
(CH3)3COCH3
(CH3)2CHOCH3
(CH3)2CHOCH2CH3

The Correct Answer and Explanation is :

2.1 Lewis Structures:

Here’s a breakdown of the Lewis structures for each compound. In these structures, each bond (single, double) and lone pairs of electrons on atoms are represented to show how atoms are bonded together. For simplicity, I’m providing the summary of the structures below without drawing each one individually, but I can help with the visuals if needed.

(a) CH2=CHOCH2CH(CH3)2

  • The structure consists of a propene group (CH2=CH) connected to an -O- (oxygen atom) attached to a butyl group with one carbon bonded to two methyl groups (CH3) attached to it.

(b) (CH3CH2)2CHCH2CH2OH

  • This structure is a hydroxyl group (-OH) attached to a 5-carbon chain with a branching methyl group (CH3) attached to the second carbon.

(c) (CH3CH2)3COH

  • This structure consists of a hydroxyl group (-OH) attached to a tertiary butyl group, where three ethyl groups (CH3CH2) are bonded to the central carbon.

(d) (CH3)2C=CHCH2CH3

  • This compound is an alkene, where a double bond (C=C) is between a secondary carbon (CH2) and a methyl group (CH3) at one end, and a butyl chain (CH2CH3) at the other.

(e) CH2=CHCH2OCH2CH(CH3)2

  • This structure contains an alkene (CH2=CH), a single bond to an oxygen atom (O), followed by a 3-carbon chain with a branching methyl group at the third carbon.

(f) (CH3CH2)2C=CH2

  • This is an alkene with two ethyl groups (CH3CH2) attached to a carbon double-bonded to another carbon (C=C).

(g) (CH3)3CCH2CH2OH

  • This structure is a tertiary alcohol, where a hydroxyl group (-OH) is attached to a two-carbon chain, and a tertiary butyl group is connected to the first carbon.

(h) CH3CH2CH2CH2CH2CH3

  • This is a straight-chain alkane (C6H14), with no branches, just a continuous chain of six carbon atoms.

(i) CH3CH2CH2OCH3

  • This is an ether (CH3O), where an ethyl group (CH2CH3) is bonded to oxygen, followed by a methyl group (CH3).

(j) (CH3CH2CH2)2CHOH

  • This is an alcohol with two ethyl groups (CH3CH2CH2) attached to a single carbon that is also bonded to a hydroxyl group (-OH).

(k) (CH3CH2)2CHCH2OCH3

  • This is an ether with a butyl chain on the left side, and an ethoxy group (-OCH3) on the right side.

(l) (CH3)2CHCH2OH

  • This structure is a primary alcohol with a 3-carbon chain, where the middle carbon is a secondary carbon, and a hydroxyl group (-OH) is attached to the terminal carbon.

2.2 Constitutional Isomers:

Constitutional isomers are compounds that have the same molecular formula but differ in the connectivity of their atoms. Let’s analyze the three compounds to identify which two are isomers:

(1) (CH3)3COCH3

  • This compound is a methylated tertiary alcohol (tert-butyl methyl ether), where a methyl group (CH3) is attached to a central oxygen atom, which is also bonded to a methyl group (CH3).

(2) (CH3)2CHOCH3

  • This compound is an ether, where a methyl group (CH3) is bonded to an oxygen atom, and the other side of the oxygen is bonded to an ethanol group (CH3CH2).

(3) (CH3)2CHOCH2CH3

  • This is another ether, similar to the second, but with a two-carbon chain (ethyl group, CH2CH3) bonded to the oxygen.

Answer:

The two compounds that are constitutional isomers are (CH3)2CHOCH3 and (CH3)2CHOCH2CH3 because they have the same molecular formula but differ in the structure of the carbon chain attached to the oxygen atom.

The first compound, (CH3)3COCH3, is not a constitutional isomer with the other two because it has a different connectivity, where the oxygen is attached to a tertiary carbon, as opposed to being connected to a two-carbon chain or an ethyl group in the other two.

Explanation:

Constitutional isomers have the same molecular formula but different arrangements of atoms. In this case:

  • Both (CH3)2CHOCH3 and (CH3)2CHOCH2CH3 contain two methyl groups attached to an oxygen, but one has a methyl group and the other an ethyl group, creating a difference in the connectivity of the atoms around the oxygen.
  • (CH3)3COCH3 differs because it has a methyl group connected to a tertiary carbon, while the other two have the oxygen attached to a more linear or branched structure involving two carbon atoms.

I can also create a visual representation of these structures if you’d like. Would you prefer that?

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