Q. 9.16 - An Introduction to General, Organic, and Biological Chemistry

Question

Calculate the number of equivalents in each of the following:

a. $1{\text{ mole of Mg}}^{2+}$

b. ${\text{0.5 mole of H}}^{+}$

c. ${\text{4 moles of Cl}}^{-}$

d. ${\text{2 moles of Fe}}^{3+}$

Step-by-Step Solution

Answer

(part a) The number of equivalents in${\text{1 mole of Mg}}^{2+}\text{= 2eq}$

(part b) The number of equivalents in ${\text{0.5 mole of H}}^{+}\text{= 0.5eq}$

(part c) The number of equivalents in ${\text{4 moles of Cl}}^{-}\text{= 4eq}$

(part d) The number of equivalents in ${\text{2 moles of Fe}}^{3+}\text{= 6eq}$

Step1: Introduction (part a).

In a chemical process, an equivalent has been the quantity of one material that people react to (or is equivalent to) an arbitrarily defined quantity of another compound. The mass of an equivalent is equivalent to its weight.

Step2: Given Information (part a).

Given:

$1{\text{ mole of Mg}}^{2+}$ 

Step3: Explanation (part a).

To compute the value of equivalents.

Each mole has two equivalents for such an ion with a charge of $2+.$ Thus the,

${\text{1 mole of Mg}}^{2+}\text{= 2eq}$

Step4: Given Information (part b).

Given:

${\text{0.5 mole of H}}^{+}$

Step5: Explanation (part b).

To compute the value of equivalents.

Each mole contains a single equivalent for just an ion with a charge of $+.$ Therefore,

${\text{0.5 mole of H}}^{+}\text{= 0.5eq}$

Step6: Given Information (part c).

Given:

${\text{4 moles of Cl}}^{-}$

Step7: Explanation (part c).

To compute the value of equivalents.

Every mole uses a single equivalent for an ion with a charge of $-.$ Thus,

${\text{4 moles of Cl}}^{-}\text{= 4eq}$

Step8: Given Information (part d).

Given:

${\text{2 moles of Fe}}^{3+}$

Step9: Explanation (part d).

To compute the value of equivalents.

There's really one equivalent with each mole of an ion with a charge of $-.$ Consequently,

${\text{2 moles of Fe}}^{3+}\text{= 6eq}$