A chemistry student needs to determine the concentration of silver nitrate (AgNO3) in a given sample from the following information:- A 10 mL sample of 0.1 M sodium chloride (NaCl) was mixed with excess silver nitrate.- The resulting precipitate was filtered, washed, and dried. The mass of the precipitate was found to be 0.212 g.- The molar mass of AgNO3 is 169.87 g/mol.What is the concentration of AgNO3 in the original sample?

Question

A chemistry student needs to determine the concentration of silver nitrate (AgNO3) in a given sample from the following information:- A 10 mL sample of 0.1 M sodium chloride (NaCl) was mixed with excess silver nitrate.- The resulting precipitate was filtered, washed, and dried. The mass of the precipitate was found to be 0.212 g.- The molar mass of Ag

Answer 1

First, we need to determine the moles of NaCl in the 10 mL sample. We can do this using the given concentration of NaCl:moles of NaCl = volume  L   concentration  M moles of NaCl = 0.010 L  0.1 M = 0.001 molesNext, we need to consider the balanced chemical equation for the reaction between NaCl and AgNO3:NaCl  aq  + AgNO3  aq   AgCl  s  + NaNO3  aq From the balanced equation, we can see that 1 mole of NaCl reacts with 1 mole of AgNO3 to produce 1 mole of AgCl. Therefore, the moles of AgCl produced are equal to the moles of NaCl:moles of AgCl = 0.001 molesNow, we can use the mass of the precipitate  AgCl  and its molar mass to determine the moles of AgCl:molar mass of AgCl = molar mass of Ag + molar mass of Cl = 107.87 g/mol  Ag  + 35.45 g/mol  Cl  = 143.32 g/molmoles of AgCl = mass of AgCl / molar mass of AgClmoles of AgCl = 0.212 g / 143.32 g/mol = 0.00148 molesSince the moles of AgCl are equal to the moles of AgNO3, we have:moles of AgNO3 = 0.00148 molesNow, we need to determine the volume of the original AgNO3 sample. Since the reaction goes to completion, the moles of AgNO3 in the original sample are equal to the moles of NaCl:moles of AgNO3 = moles of NaCl = 0.001 molesTo find the concentration of AgNO3 in the original sample, we can use the formula:concentration  M  = moles / volume  L We know the moles of AgNO3, but we need to find the volume of the original sample. Since the reaction goes to completion, the volume of the original AgNO3 sample is equal to the volume of the NaCl sample:volume of AgNO3 = volume of NaCl = 0.010 LNow, we can find the concentration of AgNO3:concentration of AgNO3 = moles of AgNO3 / volume of AgNO3concentration of AgNO3 = 0.00148 moles / 0.010 L = 0.148 MTherefore, the concentration of AgNO3 in the original sample is 0.148 M.