Chapter U2, Problem 17STP

Interpretation Introduction

Interpretation:

The condition that illustrates the statement “Like dissolves like” needs to be identified.

Concept introduction:

This concept is based on the polarity of solute and solvent molecules. The polar molecule of solvent can only dissolve in polar solvent and non-polar can only dissolve in non-polar solvent.

Answer to Problem 17STP

(B) Iodine, I₂, is more soluble in oil than water.

Explanation of Solution

Reason for correct option:

The statement “Like Dissolves Like” means polar solute molecule dissolves in polar solvent and non polar molecule of solute dissolves in non-polar solvent.

Polar solvent are hydrophilic in nature means they like water or can dissolve in water

Here, Iodine is a non-polar molecule so it dissolves more in non-polar solvent like oil.

Conclusion

Reasons for incorrect options:

(A) Iodine,I₂, is more soluble in water than KI .(Incorrect).

The water is polar in nature thus, iodine will not dissolve in water. Iodine can react with KI to form KI₃ which is soluble in water. Thus, iodine can dissolve in KI more than water.

(C) Vinegar, CH₃COOH₃ is more soluble oil than in water. (Incorrect)

Vinegar or acetic acid is polar in nature so it dissolves in water. Vinegar or acetic acid is polar in nature so it dissolves in water and not in oil.

(D) Sodium chloride, NaCl is more soluble in oil than in water. (Incorrect)

Salts form ionic bonds which are polar in nature. All salts are soluble in water because water is a polar solvent. So, NaCl is more soluble in water than oil.