A 0.2165 g sample from a powder containing an unknown
composition of chloride was dissolved in dilute
HNO3. An excess of 0.1 M
AgNO3 was added to the solution
slowly to form a precipitate. After the initial formation, the
precipitate was recrystallized by digestion, then rinsed with 0.01
M HNO3 and thoroughly dried. The
mass of the dried precipitate was 0.2640 g. Calculate (w/w)% Cl in
the unknown.
Molar mass AgNO3 = 169.87 g/mol
Molar mass NaCl = 58.44 g/mol
Molar mass AgCl = 143.32 g/mol
Molar mass Cl = 35.453 g/mol
Question 1: What are the units of the numerator
for %w/w Chloride?
Group of answer choices:
g
mg
kg
g AgCl
g Sample
g AgNO3
g Cl
g HNO3
No Units
Question 2: What are the units of the
denominator for %w/w Chloride?
Group of answer choices:
g
mg
kg
g AgCl
g Sample
g AgNO3
g Cl
g HNO3
mL H2O
No Units
Question 3: What is the mass of chloride in the
sample? (in g)
Make sure to use the right number of sig figs
Question 4: Report your determined %w/w
Chloride present in the sample.
Make sure to use appropriate sig figs