Question

Solutions of lead(II) nitrate and potassium iodide were combined in a test tube.

a. Write a molecular equation for the reaction.

b. Which of the possible products is the precipitate, and how do you know?

c. Write a complete ionic equation for the reaction and identify the spectator ions.

d. Write a net ionic equation for the reaction between lead(II) nitrate and potassium iodide.

Answer 1

a. \(Pb(NO_3)_2+2KI\rightarrow PbI_2+2KNO_3\)

Answer 2

b. Since \(KNO_3\) is soluble, \(PbI_2\) is the only product that can be the precipitate. You can also check for the solubility of \(PbI_2\) here http://periodic-table-of-elements.org/#/SOLUBILITY

Answer 3

c. \(Pb^{2+}(aq)+2NO_3^-(aq)+2K^+(aq)+2I^-(aq)\rightarrow PbI_2(s)+2K^+(aq)+2I^-(aq)\)

Answer 4

As you can see, \(K^+\) and \(NO_3^-\) are spectator ions in this reaction.

Answer 5

d. To write the net ionic equation, take the spectator ions out of the ionic equation:
\(Pb^{2}(aq)+2I^+(aq)\rightarrow PbI_2(s)\)

Answer 6

Thank you!!!