You have to prepare a pH 5.00 buffer, and you have the following 0.10 M solutions available: HCOOH, HCOONa, CH3COOH, CH3COONa, HCN, NaCN.

1. Which solution should I use?
2. How many milliliters of each solution would you use to make approximately a liter of the buffer?

You have to prepare a pH 3.50 buffer, and you have the following 0.10 M solutions available: HCOOH, CH₃COOH, H₃PO₄, HCOONa, CH₃COONa, and NaH₂PO₄. Which solutions would you use? How many milliliters of each solution would you use to make approximately 1 L of the buffer?

You have to prepare a pH 3.55 buffer, and you have the following 0.10M solutions available: HCOOH, CH3COOH, H3PO4, HCOONa, CH3COONa, and NAH2PO4. How many milliliters of HCOOH and HCOONa and would you use to make approximately a liter of the buffer?