Instructions: 

Here's how to prepare a 100mL buffer solution.  (We are certainly not sure how complex this is.)

Materials:	.3M Citric Acid
	.1M Sodium Chloride
	Distilled Water
	250 mL Beaker
	100 mL Volumetric Flask
	Balance
	Hot Plate
	Weighing Boats
		Figure 1:  Making a buffer solution

Procedure:

1.  To calculate grams of citric acid needed to make 0.3M for 100 mL, do the following.

Add the molar weights of H₃C₆H₅O₇ ·H₂O.  This will equal 210.5g per mole.

Multiply this by .3 x 100/1000 mL.  This equals 6.315 g.         

  2.  To calculate grams of sodium chloride needed to make 0.1M for 100mL, do the following.

Add the molar weights of NaCl.  This is 23 plus 35.5 to equal 58.5g per mole.

Multiply this by .1 x 100/1000mL.  This equals .585 g.

3.  Measure these amounts on the balance.  (Be sure to tare the weighing boat first.)

4.  Add measured amounts to beaker and add ~80 mL of distilled H₂0.

5.  Heat and stir to dissolve the solutes.

6.  Pour solution into the volumetric flask.  

7.  Add enough distilled H₂0 to bring the solution to 100 mL.

**YOU NOW HAVE YOUR BUFFER SOLUTION!

	Click on these sites for additional helpful information. ===>>
Figure 2:  Weighing  Carefully		A simple way to get a buffer recipe.	A good student mini-quiz.

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