What is one equivalent of an acid? What does an equivalent of a base represent? How is the equivalent weight of an acid or a base related to the substance’s molar mass? Give an example of an acid and a base that have equivalent weights equal to their molar masses. Give an example of an acid and a base that have equivalent weights that are not equal to their molar masses. What is a normal solution of an acid or a base? How is the normality of an acid or a base solution related to its molarity? Give an example of a solution whose normality is equal to its molarity, and an example of a solution whose normality is 1101 the same as its molarity.

Interpretation:

One equivalent of an acid is to be defined. An equivalent of a base is to be explained. The relation between the equivalent weight of an acid or a base and the substance’s molar mass is to be explained. An example of an acid and a base that have equivalent weights equal to their molar masses is to be stated. An example of an acid and a base that have equivalent weights that are not equal to their molar masses is to be given. The normal solution of an acid or a base is to be defined. The relation between the normality of an acid or a base solution and its molarity is to be explained. An example of a solution that has equal normality and molarity, and an example of a solution that have different normality and molarity is to be stated.

Concept Introduction:

The molarity of a solution is the molar concentration of the solution; it measures the number of moles of solute dissolved in one liter of the solution. The formula for molarity is given as,

M=nV

Where,

• n represents the number of moles of the solute.
• V represents the volume of the solution.

The normality of a solution is referred as the gram equivalent weight of a solute dissolved in one liter of the solution. The normality of solution is given as:

N=neqV

Where,

• neq represents the number of equivalents of the solute.
• V represents the volume of the solution.

One equivalent of an acid is defined as amount of the acid solution that has one mole of H+ ion. An equivalent of a base represents a base solution that has one mole of OH− ions.

The relation between the equivalent weight of an acid or a base and the substance’s molar mass is represented as,

Meq=Mmn    (1)

Where,

• Mm represents the molar mass of the substance.
• n represents the equivalence factor of the substance.
• Meq represents the equivalent weight of the substance.

The dissociation reaction of HCl in water is represented as:

HClaq→H+aq+Cl−aq

The number of H+ ion released by HCl is 1.

Hence the equivalence factor of HCl is 1 eq⋅mol−1.

The molar mass of HCl is 36.469 g⋅mol−1.

Substitute the value of Mm and n in the equation (1).

Meq=36.469 g⋅mol−11 eq⋅mol−1=36.469 g⋅eq−1

Therefore, HCl has equal molar mass and equivalent weight.

The dissociation reaction of NaOH in water is represented as,

NaOHaq→Na+aq+OH−aq

The number of OH− ion released by NaOH is 1.

Hence the equivalence factor of NaOH is 1 eq⋅mol−1.

The molar mass of NaOH is 39.9979 g⋅mol−1.

Substitute the value of Mm and n in the equation (1).

Meq=39.9979 g⋅mol−11 eq⋅mol−1=39.9979 g⋅eq−1

Therefore, NaOH has equal molar mass and equivalent weight.

The dissociation reaction of H2SO4 in water is represented as,

H2SO4aq→2H+aq+SO42−aq

The number of H+ ion released by H2SO4 is 2