Answer:
The term "normality" refers to the number of moles of a solute present in one liter of a solution, expressed as equivalents per liter (Eq/L). To calculate the normality of a solution, you need to know the molarity (moles of solute per liter of solution) and the equivalent weight of the solute. The equivalent weight of a solute is the atomic weight or molecular weight of the solute divided by the number of ions or molecules that can be formed from one molecule of the solute.
2.5 M gallium(III) hydroxide: Gallium(III) hydroxide is a basic compound and forms Ga(OH)3. One mole of Ga(OH)3 will yield three moles of hydroxide ions, so the equivalent weight of Ga(OH)3 is 1/3 of its molecular weight. Therefore, the normality of 2.5 M gallium(III) hydroxide solution is 2.5 x 3 = 7.5 N.
6.0 M barium hydroxide: Barium hydroxide is a basic compound and forms Ba(OH)2. One mole of Ba(OH)2 will yield two moles of hydroxide ions, so the equivalent weight of Ba(OH)2 is 1/2 of its molecular weight. Therefore, the normality of 6.0 M barium hydroxide solution is 6.0 x 2 = 12 N.
4.5 M sulfuric acid: Sulfuric acid is an acidic compound and forms H2SO4. One mole of H2SO4 will yield two moles of hydrogen ions, so the equivalent weight of H2SO4 is 1/2 of its molecular weight. Therefore, the normality of 4.5 M sulfuric acid solution is 4.5 x 2 = 9 N.
0.54 M iron(II) hydroxide: Iron(II) hydroxide is a basic compound and forms Fe(OH)2. One mole of Fe(OH)2 will yield two moles of hydroxide ions, so the equivalent weight of Fe(OH)2 is 1/2 of its molecular weight. Therefore, the normality of 0.54 M iron(II) hydroxide solution is 0.54 x 2 = 1.08 N.