Ionic Reaction Results

Ionic Reactions Results

B - Do your results agree with your expectations from the solubility rules/table?

Our results seemed to largely agree with the established solubility rules/table; however, a few reactions with the commonality of being mixed with Co(NO3)2 (cobalt nitrate) [reference Row A, Columns 2, 3, and 4] seemed to have such a pale pink tone that it was difficult to decide whether that could have been a precipitate or the lighting in the area where the experiment took place. Ultimately, our lab group came to the decision that no reaction occurred.

C - Which anions generally form precipitates? What are exceptions?

Results indicate that all but one of the sodium carbonate/bicarbonate mixtures produced a precipitate, the exception was when NaHCO3 was combined with Co(NO3)2 or cobalt nitrate. Furthermore, most copper and iron nitrates, even with differing sodium compounds produced a precipitate. Exceptions were Cu(NO3)2 with sodium sulfate and sodium chloride. It was also noticed that nickel, barium, and iron nitrates (excluding those with few with no reaction) across the board had the same color precipitates no matter the sodium compound that it was mixed with.
D - Which anions generally do not form precipitates?
What are the exceptions?

Sodium chloride, sodium iodide, and sodium sulfates generally do not form precipitates. One exception in our results with all three of these was when they were each combined with Fe(NO3)3 (iron nitrate) in which all three yielded brown precipitates.

E - Which cations generally do not form
precipitates?

The cations of cobalt and nickel, and even some of the other monoatomic ions including barium and copper more often than not do not form precipitates, as can be verified by the results of this experiment. One exception these all had in common was when they were combined with a phosphate, carbonate, or hydroxide.

F - Select 3 reactions that produce a precipitate, color change, or gas and write balanced chemical equation and a net ionic equation for each. Remember, a reaction may be indicated by the formation of a precipitate, color change, or the formation of gas. Record the well numbers of the precipitates you chose for your equations.

A+B- C+D-

Row A, Column 4:

Co(NO3)2 (aq) + NaCl (aq) Co(Cl)2 (s) + NaNO3 (aq)
= Co2+ (aq) + Cl- (aq) Co(Cl)2 (s)

1) Row E, Column 1:

Ni(NO3)2 (aq) + Na3PO4 (aq) Ni(PO4)2 (s) + NaNO3 (aq)
= Ni2+ (s) + PO43- (aq) Ni(PO4)2 (s)

2) Row B, Column 5:

Cu(NO3)2 (aq) + NaHCO3 (aq) Cu(HCO3)2 (s) + NaNO3 (aq)
= Cu2+ (s) + HCO3- (aq) Cu(HCO3)2 (s)