Chapter U2, Problem 5RE

(a)

Interpretation Introduction

Interpretation :

Whether methyl salicylate follows HONC 1234 rule or not must be explained.

Concept Introduction :

HONC 1234 rule is the basic rule for drawing organic molecule. The rule states that H, O, N and C generally form 1, 2, 3 and 4 bonds respectively.

Answer to Problem 5RE

Methyl salicylate follows HONC 1234 rule.

Explanation of Solution

The structure of methyl salicylate is as follows:

Each carbon has 4 bonds, each O has two bonds and each H has one bond. Thus methyl salicylate follows HONC 1234 rule.

b)

Interpretation Introduction

Interpretation :

Molecular formula of methyl salicylate must be written.

Concept Introduction :

Molecular formula is the representation of the molecule which shows the number of total number of different atoms.

Answer to Problem 5RE

Molecular formula of methyl salicylate, C₈H₈O₃ are given below.

Explanation of Solution

In methyl salicylate has total 8 carbons, 8 hydrogens and 3 oxygens. Thus, the molecular formula is C₈H₈O_3.

c)

Interpretation Introduction

Interpretation :

Overall shape of the molecule must be explained.

Concept Introduction :

Overall shape of a molecule depends on the total number of electrons including lone pair and bond pair electrons.

Answer to Problem 5RE

Methyl salicylate is planar structure with a tetrahedral methyl group. Here, all the carbon atoms are attached to 4 groups resulting in tetrahedral shape of the molecule.

Explanation of Solution

Methyl salicylate has six membered planar ring in which there are two side chains. One has hydroxyl group and another side chain has methyl ester group. Methoxy group is tetrahedral.

d)

Interpretation Introduction

Interpretation :

The oxygen atom must be found which is bonded to two carbon atoms. The reason forthe bond to be bent needs to be explained.

Concept Introduction :

Benting of bond takes place due to repulsion of electron pairs.

Answer to Problem 5RE

The oxygen shown in red is the one which is bonded with two carbon atoms. The bond is bent as there are two lone pairs on electrons. The lone pair-bond pair repulsion results in the bending of the bond.

Explanation of Solution

The oxygen shown in red has two bond pairs and two lone pairs. To minimise the repulsion among these electrons, the bond is bent.