Rohit took two different salt solutions in test tubes C and D as shown in the figure below. He added dilute HCl to each of the two test tubes. The products formed in the test tubes C and D are silver chloride and lead chloride respectively.
State:
(a) one common observation made by Rohit in both the reactions.
(b) the observations made by him on addition of excess of ammonium hydroxide to the products formed in:
1. test tube C
2. test tube D
(a) In each test tube a white precipitate is formed.
(b) 1. In test tube C, the white precipitate of silver chloride dissolves in excess ammonium hydroxide, giving a clear solution.
2. In test tube D, the white precipitate of lead(II) chloride does not dissolve in excess ammonium hydroxide and remains unchanged.
Explanation :
(a) When dilute hydrochloric acid is added to silver nitrate (AgNO3) solution in test tube C, silver chloride (AgCl) is formed, which is a white precipitate. Similarly, when dilute HCl is added to lead(II) nitrate [Pb(NO3)2] solution in test tube D, lead(II) chloride (PbCl2) is formed, which is also a white precipitate. Therefore, a common observation is the formation of a white precipitate in both test tubes.
(b) In test tube C, the white precipitate of silver chloride dissolves in excess ammonium hydroxide whereas, in test tube D, the white precipitate of lead chloride does not dissolve in excess ammonium hydroxide.
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