Question

If aqueous solutions of sodium sulfate (Na2SO4) and barium hydroxide (Ba(OH)2) are mixed, which product remains soluble?

a) Na2SO4
b) Ba(OH)2
c) Both are insoluble
d) Both are soluble

Answer 1

Sodium sulfate (Na2SO4) remains soluble when mixed with barium hydroxide (Ba(OH)2), while barium sulfate (BaSO4) precipitates as it is insoluble.

Step-by-step explanation:

When aqueous solutions of sodium sulfate (Na2SO4) and barium hydroxide (Ba(OH)2) are mixed, a double-replacement reaction occurs, which can lead to the precipitation of an insoluble salt. According to solubility rules, Na2SO4 remains soluble, but Ba(OH)2 reacts with sulfate to form barium sulfate (BaSO4), which is insoluble. The reaction that occurs is as follows:

• Ba(OH)2 (aq) + Na2SO4 (aq) → BaSO4 (s) + 2 NaOH (aq)

The sodium sulfate (Na2SO4) is a soluble compound and will remain dissolved in the aqueous solution. In contrast, barium sulfate (BaSO4) will precipitate out of the solution as it is not soluble in water.