Solid NaI is slowly added to a solution that is 0.0079 M Cu+ and 0.0087 M Ag+.Which compound will begin to precipitate first?NaICuIAgICalculate [Ag+]when CuI just begins to precipitate.×10MEnter your answer in scientific notation.What percent of Ag+ remains in solution at this point?

Answer :

AgI should precipitate first.

The concentration of when CuI just begins to precipitate is,

Percent of remains is, 0.0076 %

Explanation :

for CuI is

for AgI is

As we know that these two salts would both dissociate in the same way. So, we can say that as the Ksp value of AgI has a smaller than CuI then AgI should precipitate first.

Now we have to calculate the concentration of iodide ion.

The solubility equilibrium reaction will be:

The expression for solubility constant for this reaction will be,

Now we have to calculate the concentration of silver ion.

The solubility equilibrium reaction will be:

The expression for solubility constant for this reaction will be,

Now we have to calculate the percent of remains in solution at this point.

Percent of remains =

Percent of remains = 0.0076 %

The correct answer is C. Electrostatic repulsion between the positively charged nucleus and alpha particles. Alpha particles contain positive charges. From the principle of like charge repels like charge, these positively charged alpha particles repelled or failed to collide with the positively charged nucleus; so they bounced back from each other.