Page 10 - Pharmaceutical_Analytical_Chemistry_1_Theoretical_Notes_Level_1

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

B) Electrolytes

Strong electrolytes Weak electrolytes

✓ Substances that are completely ✓ Substances that dissociate to a small

dissociated in an aqueous solution. extent in an aqueous solution.

✓ Their solution can conduct ✓ They are weakly conductive to electric

electricity. current.

✓ e.g. NaCl and HCl ✓ e.g. acetic acid, water

Examples: Strong acid, strong -7
a) H O ionizes to only 10 M:
bases, salts of strong acid and 2 + -
H O + H O H O + OH
base. 2 (aq) 2 3 (aq) (aq)

-
+
HCl (aq) + H 2O → Cl (aq) + H 3O (aq) b) CH COOH ionizes to only 0.42%
3
w/v:
-
CH COOH + H O CH COO
3 (aq) 2 3 (aq)
+
+H O
3 (aq)
c) NH OH and HCN.
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Solubility

Solubility is a measure of how a solute will dissolve in a solvent at a constant

temperature.

❖ Soluble: can dissolve in a solvent.

❖ Insoluble: can not dissolve in a solvent.

Ionic compounds are soluble in polar solvents & have

low solubility in nonpolar solvents. E.g.: NaCl dissolves in water.

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