Chapter 8, Problem 8.4P

(a)

Interpretation Introduction

Interpretation:

The predicted boiling point of $\text{HBr}$ from the boiling points of $\text{HCl}$ and $\text{HI}$ with the use of Dobereiner’s triads is to be determined.

Concept introduction:

Dobereiner stated that all elements occur in the groups of three when arranged in the increasing order of their atomic masses. Such groups of three elements were called triads

The triads can be used to predict the chemical properties of the elements such as melting and boiling points. According to Dobereiner the boiling or melting point of the middle element can be calculated by taking the average of the first and third element in a given triad.

(b)

Interpretation Introduction

Interpretation:

The predicted boiling point of ${\text{AsH}}_3$ from the boiling points of ${\text{PH}}_3$ and ${\text{SbH}}_3$ is to be determined

Concept introduction:

Dobereiner stated that all elements occur in the groups of three when arranged in the increasing order of their atomic masses. Such groups of three elements were called triads

The triads can be used to predict the chemical properties of the elements such as melting and boiling points. According to Dobereiner the boiling or melting point of the middle element can be calculated by taking the average of the first and third element in a given triad.