In experiment 8 (part a) you will use method 2 to prepare a 50 ml buffer (buffer 2) comprising 0.5 m sodium phosphate, ph 8.0. calculate the amount in grams of nah2po4.h20 (sodium dihydrogen phosphate monohydrate, mr: 138.0); and na2hpo4 (disodium hydrogen phosphate, mr: 142.0); and select the correct answers from the dropdown boxes. calculate answer to 2 decimal places. hint: use the pka2 of 6.8 for the acid. amount (g) na2hpo4 required is amount (mass) nah2po4 required is remember to transfer the correct value to the relevant place in your lab manual as you will need this in the experiment.