Question

Q2. Write the formula of the salt you need to add to the solution of given compounds to produce a buffer solution: [15 pts] \text { a) } \mathrm{NaH}_{2} \mathrm{PO}_{4}:

\text { b) } \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{NH}_{2}: \text { c) HCN: }

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