Chapter 3, Problem 3.99P

(a)

Interpretation Introduction

Interpretation:

The balanced chemical equation for the preparation of hydroxyapatite is to be written.

Concept introduction:

In a balanced chemical equation, the total mass of reactants and products are equal in a balanced chemical equation, thus, it obeyed the law of conservation of mass. Also, the amount of substances in a balanced chemical reaction are stoichiometrically equivalent to each other.

Following are the steps to determine the moles of a chemical substance when the moles of another chemical substance present in the chemical reaction are given,

Step 1: Write the names and molecular formulas of the substances involved in the chemical reaction.

Step 2: Write the balanced chemical equation by using stoichiometric coefficients.

Step 3: Determine the molar ratio from the balanced chemical reaction between the chemical substance whose amount is given and the chemical substance whose amount is to be calculated.

Step 4: Use the molar ratio and the given amount to calculate the unknown amount of the other substance.

(b)

Interpretation Introduction

Interpretation:

The mass(g) of Hydroxyapatite $\left({\text{Ca}}_5{\left({\text{PO}}_4\right)}_3\left(\text{OH}\right)\right)$ formed from $\text{100 g}$ of $\text{Ca}{\left(\text{OH}\right)}_2$ and $\text{100 g}$ of $85\text{ \%}$ ${\text{H}}_3{\text{PO}}_4$ is to be calculated.

Concept introduction:

In a balanced chemical equation, the total mass of reactants and products are equal in a balanced chemical equation, thus, it obeyed the law of conservation of mass. Also, the amounts of substances in a balanced chemical reaction are stoichiometrically equivalent to each other.

A limiting reagent is the one that is completely consumed in a chemical reaction. The amount of product formed in any chemical reaction has to be in accordance with the limiting reagent of the reaction.

The formula to calculate moles is as follows:

  $\text{Amount}\left(\text{mol}\right)=\frac{\text{mass}}{\text{molecular mass}}$        (1)