a .2280g sample contained only NaCl and KBr. it was dissolved in water and titrated with a 0.04799M of AgNO3. complete titration of both halides was found to require 51.27mL of the AgNO3 solution. Calculate the weight percent of Cl in the solid sample.
To calculate the weight percent of Cl in the solid sample, we need to determine the moles of Cl in the titrated solution and the moles of Cl in the solid sample.
First, let's calculate the moles of AgNO3 used in the titration:
Moles of AgNO3 = concentration of AgNO3 solution (M) × volume of AgNO3 solution (L)
= 0.04799 M × 0.05127 L
≈ 0.00246 moles
Since AgNO3 reacts in a 1:1 ratio with Cl-, the moles of Cl- in the titrated solution is also 0.00246 moles.
Next, we need to determine the ratio of NaCl to KBr in the solid sample.
The molar mass of NaCl is approximately 58.44 g/mol, and the molar mass of KBr is approximately 119.0 g/mol.
Let's assume that x grams of NaCl and y grams of KBr are present in the sample.
Therefore, we have the following equations:
x + y = 0.2280 g (Total mass of the sample)
(58.44 g/mol)x + (119.0 g/mol)y = 0.00246 moles of Cl
Now, we can solve these equations using simultaneous equations.
To find the weight percent of Cl in the solid sample, we can use the following formula:
Weight percent of Cl = (mass of Cl / mass of the sample) × 100
Since we have determined the moles of Cl in the titrated solution, we can convert it to grams using the molar mass of Cl (35.45 g/mol):
Mass of Cl = moles of Cl × molar mass of Cl
= 0.00246 moles × 35.45 g/mol
To calculate the mass of the sample, we need to determine the mass of NaCl and KBr:
Mass of NaCl = x grams (Unknown)
Mass of KBr = y grams (Unknown)
With the given total mass of the sample, we can substitute the mass of NaCl and KBr into the equation:
x + y = 0.2280 g
Now we can solve these equations simultaneously to find the values of x and y.
Once we have determined the mass of Cl and the mass of the sample, we can calculate the weight percent of Cl:
Weight percent of Cl = (mass of Cl / mass of the sample) × 100
By calculating these values, we can find the weight percent of Cl in the solid sample.
To calculate the weight percent of Cl in the solid sample, we need to find the amount of Cl present in the sample, and then divide it by the total weight of the sample. Here's how you can do it step by step:
1. Calculate the number of moles of AgNO3 used in the titration:
Moles of AgNO3 = volume of AgNO3 solution (in L) × concentration of AgNO3 (in mol/L)
Moles of AgNO3 = 51.27 mL × 0.04799 mol/L / 1000 mL/L = 0.002467 mol
2. Determine the number of moles of Cl ions reacting with AgNO3:
According to the balanced chemical equation between AgNO3 and NaCl:
AgNO3 + NaCl → AgCl + NaNO3
The stoichiometry of the reaction tells us that 1 mole of AgNO3 reacts with 1 mole of Cl ions.
Therefore, the number of moles of Cl ions = 0.002467 mol
3. Convert the moles of Cl ions to grams of Cl:
The molar mass of Cl is 35.45 g/mol, so:
Mass of Cl = moles of Cl ions × molar mass of Cl
Mass of Cl = 0.002467 mol × 35.45 g/mol = 0.08726 g
4. Calculate the weight percent of Cl in the sample:
Weight percent of Cl = (Mass of Cl / Mass of sample) × 100
The mass of the sample is given as 0.2280 g
Weight percent of Cl = (0.08726 g / 0.2280 g) × 100 = 38.23%
Therefore, the weight percent of Cl in the solid sample is approximately 38.23%.