Page 52 - Pharmaceutical_Analytical_Chemistry_1_Theoretical_Notes_Level_1

Mansoura National University
Pharm D-Clinical Pharmacy Program Level 1 Pharm. Anal. Chem. 1 (PC 101)

➢ Let's look at H 2SO 4

2-
+
H 2S0 4 → 2 H + 1 (SO 4)
• Each molecule of H 2SO 4 would give 2 H and 1 (SO 4)
+
2-
• If I had 100 mL of a 1 M H 2SO 4:

+
2-
I would have 0.10 moles of (SO 4) and 0.20 moles of H Why?
+
• 1 mole of H 2SO 4 has 2 moles of H

1 M HCl = 1 N HCl

1 M H 2(SO 4) = 2 N H 2(SO 4)

1 M H 3(PO 4) = 3 N H 3(PO 4)

1 M Ca(OH) 2 = 2 N Ca(OH) 2

+
• For every mole of sulfuric acid, you would get 2 moles of H
• For every mole of calcium hydroxide, would get 2 moles of hydroxide ions

Relation between Molecular & Equivalent Weight and between Molarity &
Normality of the same solution
Equivalent Weight = Normality = Molarity × n

n denotes the number of equivalents.
Example: For H SO in acid-base reactions
2 4
Equiv. Weight of H SO = Mol. Weight of H SO / 2
2 4 2 4

While Normality of H SO solution = Molarity x 2
2 4
(Normality of 1 M H SO = Molarity x 2 = 1 x 2 = 2 N)
2 4

1 Mole H 2SO 4  2 Equiv. weights

Quiz

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