Chapter 14, Problem 12STP

Interpretation Introduction

Interpretation:

The compound that can hold more solute among NaCl and KCl at 20°C needs to be determined. The solubilities need to be compared from the graph.

Concept introduction:

Solubility can be defined as maximum amount of solute that can dissolve in known amount of solvent at a given temperature and pressure. During solution formation, solute and solvent particles collide with each other, so that the solute gets dissolves in solvent. When temperature is increased, it can affect solubility of a solute in solvent. This is because increase in temperature, increases the kinetic energy which results in more frequent collisions.

Answer to Problem 12STP

At 20°C, the NaCl solution can hold more solute. At 80°C, the solubilities are reversed and KCl is more soluble than NaCl.

In that graph, at 20 °C, the solubility of NaCl is higher than KCl. Therefore more amount of NaCl can be dissolved than KCl in 100 gm water at 20 °C. But when temperature is increased, the graph is showing totally reverse effect. At 80°C, the solubilities are reversed and KCl is more soluble than NaCl.

Explanation of Solution

In that graph, at 20 °C, the solubility of NaCl is higher than KCl. Therefore more amount of NaCl can be dissolved than KCl in 100 gm water at 20 °C. But when temperature is increased, the graph is showing totally reverse effect. At 80°C, the solubilities are reversed and KCl is more soluble than NaCl.