Question

Explain why the solutions of SbCl3(aq) in our lab also contain HCl. Why would adding a few drops of this solution to 300 mL of water result in a foggy or cloudy appearance?

Answer 1

Here's what I get

Step-by-step explanation:

SbCl₃ reacts with water to form slightly soluble antimony oxychloride.

SbCl₃(aq) +H₂O(ℓ) ⇌ SbOCl(s) + 2HCl(aq)

Your observation is an example of Le Châtelier's Principle in action,

The SbCl₃(aq) in your lab has enough HCl added to push the position of equilibrium to the left and keep the SbOCl in solution.

If a few drops of the SbCl₃(aq) were added to 300 mL of water, the solution would turn cloudy. The HCl would be so dilute that the position of equilibrium would lie to the right, and a cloudy precipitate of antimony oxychloride would form.