a group IV unknown gave no precipitate with (NH4)2SO4 or with NH3/(NH4)2C2O4. Th

Question

a group IV unknown gave no precipitate with (NH4)2SO4 or with NH3/(NH4)2C2O4. The addition of Na2HPO4 to the solution produced a white precipitate. The precipitate was dissolved in HCl and NaOH was added. A blue-colored precipitate resulted. Write net ionic equations for the three reactions that were observed.

Based on the information given, I think that Magnesium is present? What are the equations?

GROUP IV PRELAB A Group IV unknown gave no precipitate with (NHs) SO, or with NHs/(NH4)CO. The addition of Na2HPO4 to the solution produced a white precipitate. The precipitate was dissolved in HCl, and NaOH was added. A blue-colored precipitate resulted. Write net ionic equations for the three reactions that were observed.

Explanation / Answer

Since the cation doesn't form any precipitation with (NH4)2SO4 or NH3/(NH4)2C2O4 it is clear that the cation is Mg2+.

1.Reaction with Na2HPO4:

When Mg2+ reacts with Na2HPO4, MgNH4PO4(s) is formed. The net ionic reaction is

(a): Mg2+(aq) + NH3(aq) + HPO42-(aq) --------- > MgNH4PO4(s)

2.Reaction of HCl:

MgNH4PO4(s) + 2H+(aq) ------- > Mg2+(aq) + NH4+(aq) + H2PO4-(aq)

3. Reaction with NaOH and dye:

Mg2+(aq) + 2OH-(aq) ------ > Mg(OH)2(s)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.