Chapter 8.2, Problem 35SSC

Interpretation Introduction

Interpretation:

The molecular formula of the given compounds needs to be determined.

Concept introduction:

1. Molecular formula can be written by taking the numbers (which are written as the prefixes to the respective elements in the nomenclature) and adding them as suffixes in the formula.

2. Acids containing binary elements are named as hydro $+$ stem $+$ ic, where hydro is cation and stem is anion and it gives molecular formula by balancing charges upon them.

3. Acids containing poly atomic groups are named as stem $+$ ic where stem $+$ ate or stem $+$ ite acts as anion. The molecular formula is obtained by balancing charges upon them.

Answer to Problem 35SSC

Molecular formula of compounds will be:

Iodic acid $\to HI{O}_3$

Disulfur trioxide $\to S_2{O}_3$

Dinitrogen monoxide $\to N_{2}O$

Hydrofluoric acid $\to HF$

Explanation of Solution

Iodic acid is a poly atomic acid hence stem $+$ ate i.e. iodate $\left(I{O}_3{}^{-}\right)$ acts as anion and hydrogen as cation.

Balancing the charges will give formula as $HI{O}_3$.

Disulphuric trioxide’s formula can be written using the concept (1)

disulphur $\to 2$ sulphur; trioxide $\to 3$ oxygen atoms thus, the formula is $S_2{O}_3\left(di=2;tri=3\right)$

Dinitrogen monoxide's formula can be written using the concept (1)

dinitrogen $\to 2$ Nitrogen, monoxide $\to 1$ oxygen thus, the formula will be $N_{2}O\left(di=2;mono=1\right)$

Hydroflouric acid is a binary element containing acid in which hydrogen is cation and fluorine is anion. Thus, the formula is

$H^{+}{F}^{-}$

Or,

HF

Conclusion

Iodic acid $\to HI{O}_3$

Disulfur trioxide $\to S_2{O}_3$

Dinitrogen monoxide $\to N_{2}O$

Hydrofluoric acid $\to HF$