Question

41.
Silver nitrate (AgNO3) solution with sodium chloride (NaCl) forms a white
colloidal AgCl, Predict the charge on the colloidal AgCl when the amount of
AgNO, is lower than the amount of NaCl.
(A) Neutral
(B) Positive
(C) Negative
(D) Zwitter lonic​

Answer 1

Answer:

(C) Negative

Explanation:

As AgCl is precipitated and we have NaCl in eccess means Na+ and Cl- ion but precipitated compound has Ag+ and Cl- so Cl- ion is common thus collidal will be negatively charged.

Answer 2

Answer:

negative

Explanation:

The most important thing you have to remember is that the common ion gets adsorbed and that is the charge on the sol.

AgNO3 + NaCl → AgCl (ppt.) + NaNO3

But since it is mentioned that we have NaCl in excess, the common ion here becomes Cl. That means Cl −  will get adsorbed. So the sol now becomes (AgCl)Cl which will be a negatively charged sol.

Note: If AgNO3 is taken excess then we have Ag+ as the common ion which will get adsorbed forming the sol Ag(AgCl) which will be positively charged due to the positive charge on Ag+ ion.