Chapter 10, Problem 7MCP

(a)

Interpretation Introduction

Interpretation:

Representation of the given molecule is structural formula has to be given true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

The given representation is not a structural formula.  Hence, the given structural representation is false.  This is a line formula representation.  In structural formula representation, all the atoms are bonds are explicitly shown.

(b)

Interpretation Introduction

Interpretation:

Molecular formula for the given structure is ${\text{C}}_{\text{4}}{\text{H}}_{\text{9}}\text{OH}$ has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

Given molecular formula is a false one.  This is because, there are a total of three carbon atoms that is indicated by the intersection of lines and the end-point.  The correct molecular formula is ${\text{C}}_{\text{3}}{\text{H}}_{\text{7}}\text{OH}$.

(c)

Interpretation Introduction

Interpretation:

Molar mass of the given structure is $\text{76}\text{g/mol}$ has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

The molecular formula is ${\text{C}}_{\text{3}}{\text{H}}_{\text{7}}\text{OH}$.  Molar mass can be calculated as shown below,

    $\begin{array}{l}\text{Molar}\text{mass}\text{=}\text{3(12}\text{.01)}\text{+}\text{8(1}\text{.008)}\text{+}\text{1(16}\text{.00)}\\ \text{=}\text{36}\text{.03}\text{+}\text{8}\text{.064}\text{+}\text{16}\text{.00}\\ \text{=}\text{60}\text{.094}\text{g/mol}\end{array}$

Given molar mass is $\text{76}\text{g/mol}$.  This is a false one as the correct molar mass is found to be $\text{60}\text{g/mol}$.

(d)

Interpretation Introduction

Interpretation:

Given structure is a substituted alkane has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

As hydroxyl group is bonded to a carbon atom, it is not a substituted alkane.  It is an alcohol.  Hence, the given statement is false.

(e)

Interpretation Introduction

Interpretation:

Given structure polar has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

As hydroxyl group is present in the above structure, it is a polar compound.  This is because hydroxyl group is polar.  Therefore, the given statement is true.

(f)

Interpretation Introduction

Interpretation:

Carboxyl group is present in the given structure has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

Given statement is false.  This is because there is no carboxyl group present in the structure.  Only one hydroxyl group is present.

(g)

Interpretation Introduction

Interpretation:

IUPAC name is 1-butanol for the given structure has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

Longest carbon chain contains three carbon atoms.  An hydroxyl group is present in the compound.  Hence, the IUPAC name of the given compound is 1-propanol and not 1-butanol.  Therefore, the given statement is false.

(h)

Interpretation Introduction

Interpretation:

Given structure is more soluble than butane has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

Butane is a hydrocarbon.  This does not have any polar groups in it.  But the given structure has got a polar hydroxyl group in it.  Therefore, the solubility of 1-propanol will be more than that of butane.  Hence, the given statement is true.

(i)

Interpretation Introduction

Interpretation:

Given structure is higher boiling point than butane has to be given as true or false and if it is a false statement, the reason has to be described.

Explanation of Solution

Given molecule structure is,

Butane is a hydrocarbon.  Given structure has a polar group in it.  In butane there will be less intermolecular attraction compared to the given structure that has polar groups.  In the given structure, the hydroxyl group present can involve in hydrogen bonding with other molecules.  Hence, the given compound will have higher boiling point than butane.  This implies that the given statement is true.