Question

5. Phosphate serves as the intracellular buffer. Its ionization is shown below. H3PO4 + H,PO HPO 2 + H + HPO.-- +PO3 + H PK, = 2.14 pK, = 6.86 PK, = 12.4 What ionic forms would be present in the cell at pH 7? A. All forms would be present. B. HPO and PO43- C. H PO, and HPO 2- D. HPO4 E. H2PO4

Answer 1

H₂PO4 H₂PO4 the bka = 2:14 H₂ PO 4 ² HPO4 +HT pka = 6.86 HPO ² PO43 +H* pka = 12.4 If the pH of solution is greater than pka of acid, then that acid loss its proton and remain in deprotonated form. at pH=7 , H₂ POA & upo forms present in cell. First peas of H₂PO4 is 2.14 so it converted to H₂PO4 completely since pH=7 so H₂PO4 also loss its proton Converted to its conjugate base HP Oft. does its greater not lose broton But 4po 4² as its pra than pro AS present so In optionc solution correct H₂PO4 A HPO4 Answer.