A buffer is a substance that consists of
acid and base forms in solution and which minimizes changes in pH when
additional acids or bases are added to the solution.
Here's how to prepare a 100mL buffer solution. (We are certainly not sure how complex this is.)
1. To calculate grams of citric acid needed to make 0.3M for 100 mL, do the following.
Add the molar weights of H3C6H5O7 ĚH2O. 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!