Question

During the experiment a student precipitated and digested the BaSO4. After allowing the precipitate to settle, they added a few drops of BaCl2 solution, and the previously clear solution became cloudy. Explain what happened.

Answer 1

Answer:

Incomplete precipitation of barium sulfate

Explanation:

The student has precipitated and digested the barium sulfate on his/her side. But on the addition of $BaCl_2$ in the solution, the solution become cloudy. This happened because incomplete precipitation of barium sulfate by the student. When $BaCl_2$ is added, there are still sulfate ions present in the solution with combines with $BaCl_2$ and forms $BaSO_4$ and the formation of this precipitate makes the solution cloudy.