Chapter 13.3, Problem 1CP

Interpretation Introduction

Interpretation:

Theconcentration that does not change on heating a solution to 75°Cis to be identified.

Concept introduction:

The number of grams of solute present in $100g$ of solution is called percent by mass of the solution.

Percent by mass of a solution is obtained by dividing the mass of solute by the mass of solution (i.e., mass of solute and mass of solvent), which is then multiplied by $100\%$.

Mathematically, the percent by mass of a substance is written as

$\text{Percent by mass}=\frac{\text{mass of solute}}{\text{mass of solute}+\text{mass of solvent}}\times 100\%$

Molarity is the number of moles of solute that present in one litre of solution.

Mathematically, it can be expressed as follows:

$\text{Molarity }\left(M\right)=\frac{\text{moles of solute}}{\text{litre of solution }}$

Mole fraction is defined as the ratio of number of moles of given component to total number of moles of solution.

Mathematically mole fraction of component A can be expressed as follows:

${\chi }_{\text{A}}=\frac{\text{moles of component A}}{\text{Sum of moles oa all component}}$

Molality is defined as number of moles that present in one kilogram of the solvent.

Mathematically, it can be expressed as follows:

$\text{Molality }\left(m\right)=\frac{\text{moles of solute}}{\text{mass of solvent }\left(\text{in Kg}\right)}$

Moles of the solute and mass of the solvent are not affected by temperature.