Question

Excess Ag+ is added to 50 mL of NaBr soln and precipitated out 22.8 mg of AgBr. What is the original concentration of Br- ion in the solution in ppm?

Answer 1

Convert 22.8 mg AgBr to moles. moles = grams/molar mass.

Since 1 Br^- is in 1 molecule of AgBr, that must be the moles Br^- in the 50 mL.

Convert moles Br^- to grams in the 50 mL.
Now I would convert that to mg/L which will make it in ppm.

Answer 2

.005