Questions 22-24 refer to the following information. A group of students was asked to recover Cu(s) f — Acids and Bases Chemistry Question
Question
Questions 22-24 refer to the following information.
A group of students was asked to recover Cu(s) from a blue-green aqueous solution containing an unknown concentration of Cu2+(aq). The students took a 100.0 mL sample of the solution and added an excess of 1.0 M Na3PO4(aq), causing the Cu2+(aq) to precipitate as Cu3(PO4)2(s), as shown in step 1 below.
Step 1: [VISUAL]
The Cu3(PO4)2(s) was filtered, dried, and weighed. Then the Cu3(PO4)2(s) was dissolved in a 3.0 M HCl(aq) solution, as shown in step 2 below.
Step 2: [VISUAL]
The students added a strip of Zn(s) to the solution to recover the Cu(s) as shown in step 3 below.
Step 3: [VISUAL]
Finally, the Cu(s) was filtered, dried, and weighed.
[VISUAL]
- The values of the dissociation constants for H3PO4 are given in the table above. Given that the solution in the beaker at the end of step 2 had a pH of approximately 1, which of the following chemical species had the lowest concentration among the products of step 2 ?
H+(aq)
H2PO4−(aq)
HPO42−(aq)
PO43−(aq)