Which of the following ion has the highest coagulation power for the sol. Which is obtained by the following reaction?
`FeCl_(3)("excess")+NaOHtoSol`

Options

A. `Al^(3+)`
B. `SO_(4)^(2-)`
C. `l^(-)`
D. `Na^(+)`

Answer

B

Explanation

The sol becomes positively charged dur to excess of `Fe^(3+)` ions.