Chapter 15.2, Problem 17LC

Interpretation Introduction

Interpretation: The substances which are dissolve to a significant extent in water needs to be determined.

Concept Introduction: The solubility of one substance in other depends on the interactions between the solvent and solute. The dissolution of a solute in solvent is based on the principle of like dissolve like. Therefore, polar solutes are soluble in polar solvents and non-polar solutes are stable in non-polar solvents.

Explanation of Solution

Reason for correct option/s:

Water is a polar solvent thus; it will only dissolve polar solute. Thus, the substances which are polar in nature can only dissolve in water. From the given options, $\text{KCl}$ , ${\text{MgSO}}_{\text{4}}$ , sucrose and ${\text{NaHCO}}_{\text{3}}$ are polar in nature thus, they are soluble in water. Therefore, options (b), (d), (e) and (f) are correct options.

Conclusion

Reason for incorrect option/s:

Water being a polar molecule can only dissolve polar substances. Thus, non-polar substances cannot be dissolved in water. From the given option, ${\text{CH}}_{\text{4}}$ and ${\text{I}}_{\text{2}}$ are non-polar as there is no significant difference between the electronegativity of two atoms. Therefore, option (a) and (c) are incorrect options.