To determine the chloride content of an unknown soluble chloride salt, a student dissolves 0.4250 g of the salt in water and adds excess 0.10 M AgNO3. A white precipitate forms, which is filtered onto pre-weighed filter paper, washed with cold water, and dried to constant mass. Mass of dried precipitate = 0.8610 g.
The student does not dry the AgCl precipitate to constant mass before weighing. How will this affect the calculated %Cl?
- Acheck_circle
Calculated %Cl is too high
- B
Calculated %Cl is too low
- C
No effect on %Cl
- D
%Cl reported as zero
Explanation
Residual water increases the precipitate mass, making moles Cl- appear larger and %Cl too high.