UMM AL-QURA UNIVERSITYFACULTY OF MEDICINEDEP. OF BIOCHEMISTRY

بسم الله الرحمن الرحيم

OBJECTIVES:

Training the student about: Use of the analytical balance. Volumetric glassware measurement. Use of digital and glass pipettes. Ideal preparation of different types of

solutions (Standard, Saturated, Unsaturated and Percent solutions).

DEFINITIONS:

Normality (g eq/L): The concentration of a solution in

equivalents per liter. Molality (W/W): Mole (mol.): A mass of a pure substance

equal to its formula weight in grams (g). Molarity (W/V): The concentration of a solution in units

of moles of solute per liter of solution.

In case of solids: 1 molar solution=M.W in

gms.x100/purity%g/l. Example: 1 molar solution of NaOH: =40 x 100/96.0 g/l. In case of liquids: 1 molar solution=M.W x 100/purity x

Sp.Gr. g/l. Example: 1 molar solution of acetic acid: = 60.05 x 100/99.5 x 1.049 g/l.

EXPERIMENT 1:THE USE OF ANALYTICAL BALANCE.

Take two conical flasks. Place distilled water in one flask and

tape water in the other. Weigh 5 ml. of water six times from

each flask using the analytical balance. Express your results in the table.

or=

C.V. (Co. Var.)% = x 100

EXPERIMENT 2:ASSESSMENT OF NORMALITY AND MOLARITY

o Read the given details of the reagent from its bottle:

o M.W.o Sp. Gr. / or wt/v at 20 c.o Purity %o Prepare the given table:

EXPERIMENT 3:PREPARATION OF STANDARD SOLUTIONS.

Prepare 250 ml. of 2M HCl. And NaOH solutions (see the table above).

Keep the solutions for the next practical.

EXPERIMENT 4:PREPARATION OF SATURATED SOLUTIONS.

Prepare 20 ml. of saturated solution of Sodium chloride and Ammonium sulphate.

Prepare 100 ml. of percent solutions of Sodium chloride and Ammonium sulphate.

(5%, 10%, 12% and 15%).

Experiment 5:Preparation of Percent Solutions.

ABDULLATIF TAHA ABDULLAMSC. BIOCHEMISTRY

QUESTIONS?