City Uiversity of New Yok Deaet of 6) Consider the following: PO I HPO,2 H,PO The term amphiprotic can be used to describe A. I only B. II and III only C. I, II and III only D. 11, 111 and Ⅳ only. 7) An aqueous solution of will produce a basic solution. a. NaCI b. NazSO4 c. NaHSO4 d. KBr e. NH CI04 Ka 7.2 × 10-3 6.3 x 10 4.2 × 10-13 8) Acid H3PO4 H2PO4- HPO, 2- Using the information above, choose the best answer for preparing a buffer with pH-7 a. H3PO4 c. K2HPO4 + KH2PO4 d. K3PO4 e. K2HP04+H3PO4 9) The net ionic equation for the reaction between aqueous solutions of HF and KOH is GenC hem2 Summer 2017 Exam I Versson B
6) amphiprotic is a compound which can accept and donate protons. In the options PO43- cant donate protons, HPO42- and H2PO42- are can donate protons and accept protons, so they are amphiprotic compounds while H3PO4 cant takes protons. Answer is B.
7) Answer is B. Aqueous solution of NaCl produce NaOH and HCl these are strong acid and strong base which gives neutralization
Aqueous solution Na2SO4 Produce 2NaOH and H2SO4 strong base of 2 moles and strong acid of one mole and weak acid of one mole. So the resulting solution will be basic.
, Aqueous solution NaHSO4 produce NaOH and H2SO4 and Aqueous solution KBr produce KOH and HBr. In these compounds produce strong base and strong acid. So they neutralize each other. While NH4ClO4 gives NH4OH and HClO4 which are weak base and strong acid and the resulting solution is acidic.
8) Answer is C. If we use H3PO4 and and K2HPO4+H3PO4 are acidic buffers. K2HPO4+KH2PO4 can make neutral buffer solution of Ph 7 while K2HPO4+K3PO4 and K3PO4 can become basic buffer solutions.
9. The net ionic reaction is HF + OH- = H2O + F-. This is because HF is a weak acid that doesn’t dissociate completely in water. So the answer is B.