Determining buffering capacity of phosphoric acid and resulting Pi buffer.
3.1 Take 25ml of 50mM H3PO4 into a 50ml beaker.
3.2 Stir the solution with a magnetic flea and read the pH.
3.3 Add 0.2ml portions of 1M NaOH (approximate) mixing well and
reading the pH after each addition.
3.4 Plot the result on a graph with volume of NaOH on the ―x‖ axis and
pH on the ―y‖ axis.
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3.5 Repeat 3.1 – 3.4 using the Pi buffer obtained from 1 and titrate with 1M NaOH or HCl. Observe the property of the buffer in resisting the pH change.