Chapter 3, Problem 3.117SP

(a)

Interpretation Introduction

Interpretation:

The price of ${\text{K}}_{\text{2}}{\text{SO}}_{\text{4}}$ (dollar per kilogram) to supply the same amount of potassium of $\text{KCl}$ on dollar basis has to be determined.

Concept Introduction:

• Mass percentage of an element of a compound is the ratio of total mass of that element to the mass of whole compound and multiplied with hundred.
• Equation for Number of moles of a substance, from its given mass is,

    $\text{Number of moles}\text{=}\frac{\text{Given}\text{mass}}{\text{Molar}\text{mass}}$

• Number of grams of a substance from its number of moles is,

        $\text{Number of moles}\text{×}\text{Molecular}\text{mass in grams}\text{=}\text{Number}\text{of}\text{grams}$

(b)

Interpretation Introduction

Interpretation:

The mass of ${\text{K}}_2\text{O}$ contains the same number of moles of potassium atoms as 1.00 kg of $\text{KCl}$ has to be calculated.

Concept Introduction:

• Mass percentage of an element of a compound is the ratio of total mass of that element to the mass of whole compound and multiplied with hundred.
• Equation for Number of moles of a substance, from its given mass is,

    $\text{Number of moles}\text{=}\frac{\text{Given}\text{mass}}{\text{Molar}\text{mass}}$

• Number of grams of a substance from its number of moles is,

        $\text{Number of moles}\text{×}\text{Molecular}\text{mass in grams}\text{=}\text{Number}\text{of}\text{grams}$