In a nickel bath with a total volume of 1000 gallons, titration of a 50 milliliter sample with 0.1 N silver nitrate used up 10.5 milliliters to the end point. What is the concentration in ounces per gallon of the nickel chloride (NiCl2 ) in the bath?
To find the concentration of nickel chloride (NiCl2) in the bath, we can use the results of the titration and the volume information. Here's how:
Step 1: Calculate the number of moles of silver nitrate used in the titration.
The concentration of silver nitrate is given as 0.1 N (normality). 1 N solution contains 1 gram equivalent weight of the solute per liter of solution. Since the molecular weight of silver nitrate (AgNO3) is 169.87 g/mol and it has a 1:1 stoichiometric ratio with nickel chloride (NiCl2), we can say its equivalent weight is also 169.87 g/mol.
First, convert the volume of silver nitrate used in the titration from milliliters to liters:
50 milliliters = 0.05 liters
Next, calculate the number of moles of silver nitrate (AgNO3):
moles of AgNO3 = concentration (N) * volume (L)
moles of AgNO3 = 0.1 N * 0.05 L = 0.005 moles
Step 2: Calculate the number of moles of nickel chloride (NiCl2) present in the 0.05 L sample.
Since nickel chloride has a 1:1 stoichiometric ratio with silver nitrate, the number of moles of nickel chloride is the same as the number of moles of silver nitrate:
moles of NiCl2 = moles of AgNO3 = 0.005 moles
Step 3: Calculate the number of moles of nickel chloride per gallon.
The total volume of the bath is given as 1000 gallons. Therefore, the number of moles of nickel chloride per gallon is:
moles of NiCl2 per gallon = moles of NiCl2 / total volume
moles of NiCl2 per gallon = 0.005 moles / 1000 gallons = 5 x 10^-6 moles/gallon
Step 4: Convert moles per gallon to concentration in ounces per gallon.
The molar mass of nickel chloride (NiCl2) is 129.60 g/mol. To convert moles per gallon to ounces per gallon, we use the conversion factor: 1 mole = 85.74 ounces.
concentration (ounces/gallon) = moles per gallon * molar mass (ounces/mole)
concentration (ounces/gallon) = 5 x 10^-6 moles/gallon * 85.74 ounces/mole
concentration (ounces/gallon) = 4.287 x 10^-4 ounces/gallon
Therefore, the concentration of nickel chloride (NiCl2) in the bath is approximately 4.287 x 10^-4 ounces per gallon.