posted by amy on .
A solution contains 0.245 of dissolved lead (lead ion or Pb2+.)
How many moles of sodium chloride must be added to the solution to completely precipitate all of the dissolved lead?
What mass of sodium chloride must be added?
Pb^+2 + 2NaCl --> PbCl2 + 2Na^+
Convert 0.245 g Pb^+2 to moles. moles = grams/molar mass
Using the coefficients in the balanced equation, convert moles Pb to moles NaCl. That gives you part a.
Convert moles NaCl to grams. g = moles x molar mass. That gives you part b.