Chapter 4.1, Problem 4.1BFP

(a)

Interpretation Introduction

Interpretation:

The two formula units of the strong electrolyte sodium phosphate dissolved in water is to be drawn.

Concept introduction:

A solution is a combination of two parts: solute and solvent. A solute is the substance that is present in small quantity and solvent is the substance in which solute is dissolved. When water acts as a solvent then it is known as an aqueous solution.

An electrolyte is a substance that conducts electricity when it is dissolved in water. Ionic compounds like sodium phosphate $\left({\text{Na}}_3{\text{PO}}_4\right)$ are examples of electrolyte.

(b)

Interpretation Introduction

Interpretation:

The moles of ions when $0.40\text{}\text{mol}$ of sodium phosphate is dissolved in water are to be calculated.

Concept introduction:

The SI unit for amount of substance is $\text{mol}$. One mole is defined as the amount of substance that contains the same number of entities such as molecules, ions, atoms as the number of atoms in $12\text{g}$ of $\text{C}-12$.

The expression to calculate the moles of ions $\left(\text{mol}\right)$ in a compound is as follows:

$\text{moles of ions}=\left(\text{moles of compound}\left(\text{mol}\right)\right)\left(\frac{\text{number of mol of ion}}{1\text{mole of compound}}\right)$