Chapter 3, Problem 3.106P

(a)

Interpretation Introduction

Interpretation:

The overall balanced equation associated with Iron smelting process is to be written.

Concept introduction:

Smelting is essentially a process where a metal particularly iron is extracted from its ore at elevated temperatures. This is carried to out in blast furnaces where the first step involves melting the metal out of its ore followed by combining it with a reducing agent to decompose the ore. The latter is done using a source of Carbon such as Coke.

The purpose of using carbon is that being a reducing agent it removes the oxygen from the ore and the metal can thus be extracted. This oxidation step is carried out in two stages, producing carbon monoxide and Carbon dioxide.

Balancing the equation follows the usual law of conservation of mass the total mass of reactants and products are equal in a balanced chemical equation.

Following are the steps to write a balanced chemical equation.

Step 1: Translate the chemical statement into a skeleton equation. The reactants are the chemical substances that undergo a change, thus, write the reactants on the left side of the yield arrow. The products are the chemical substances that are produced during the chemical change, thus, write the products on the right side of the yield arrow. Put a blank before each formula while beginning the balancing process.

Step 2: Identify the most complex substance and choose an element such that the element must be present only in one reactant and one product. Place the stoichiometric coefficient before the element/elements such that the number of atoms of that element(s) is the same on both sides.

Step 3: Balance the remaining atoms by placing the stoichiometric coefficients before the element/elements such that the number of atoms of that element(s) is the same on both sides. Identify the least complex substance and end with it.

Step 4: In a balanced chemical reaction, the smallest whole number coefficients are most preferred. Hence, adjusting the coefficients in such a way that the smallest whole number coefficients are obtained for each element.

Step 5: Check whether the chemical equation is balanced or not by counting the number of atoms of each element on both sides.

Step 6: Specify the states of matter of each chemical substance present in the balanced chemical equation.

(b)

Interpretation Introduction

Interpretation:

Mass of carbon monoxide required to form 45.0 metric tons of iron from ferric oxide is to be calculated.

Concept introduction:

No. of moles is calculated by the formula:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molecular mass (g)}}$        (1)

The formula to calculate the mass is,

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molecular mass}\right)\left(\text{number of moles}\right)$        (2)

The conversion factors for converting metric tons to kilograms is,

  $1\text{ metric ton}={\text{10}}^3\text{ kg}$

The conversion factors for converting kilograms to grams is,

  $1\text{ kg}=\text{1000}\text{}\text{ g}$