In: Chemistry
2. Considering the amphoteric behavior of H2PO4-, the above comparison may or may not correct. Instead, let us compare based on pH of these two at the same concentration. Do not forget the amphoteric behavior of H2PO4-:
a. What is the pH of 0.1 M H2PO4- (for example, 0.1 M NaH2PO4)?
b. What is the pH of 0.1 M NH4+ (for example, 0.1 M NH4Cl)?
c. Which one is more acidic?
d. Does pH of NaH2PO4 change if its concentration changes? How about NH4Cl?
e. At what concentration NH4Cl will have the same pH as NaH2PO4? is this concentration realistic?
f. Based on pH calculation, which one is more acidic, H2PO4- or NH4+?
c) H2PO4^2- is more acidic as has produced more concentration of H3O+.
d) yes pH changes with change in concentration of both aciids.