I have a 0.00156 M solution of CuSO4*5H2O in water (from 0.0398 g of CuSO4*5H20 in 100 mL of water). How would I calculate the ppm of Cu of that solution from that information?
You have 0.0398 g CuSO4.5H2O. Convert that to g Cu as follows:
0.0398 x (atomic mass Cu/molar mass CuSO4.5H2O) = ?
That gives you g Cu/100 mL (technically, that should be 100 mL OF SOLUTION. Then convert 0.0398 g Cu to mg Cu which is in 100 mL of solution then multiply by 10 to find mg Cu/L of solution and that is ppm of Cu.
Now if I were to find ppm of Cu in different aliquots of this stock solution (5 mL, 10 mL, etc.) how would I go about that?
To calculate the parts per million (ppm) of copper (Cu) in the solution, you need to determine the amount of Cu in the solution and then convert it to ppm. Here is how you can do it:
1. Calculate the amount of CuSO4*5H2O in moles:
- Given the molar mass of CuSO4*5H2O is 249.68 g/mol, calculate the number of moles of CuSO4*5H2O using the mass of CuSO4*5H2O (0.0398 g).
Moles of CuSO4*5H2O = mass of CuSO4*5H2O / molar mass of CuSO4*5H2O
= 0.0398 g / 249.68 g/mol
2. Calculate the amount of Cu in moles:
- CuSO4*5H2O has a 1:1 stoichiometric ratio of Cu to CuSO4*5H2O, so the moles of Cu will be the same as the moles of CuSO4*5H2O.
Moles of Cu = Moles of CuSO4*5H2O
3. Calculate the concentration of Cu in the solution:
- Given the volume of the solution is 100 mL (0.100 L), calculate the molarity (M) of Cu by dividing the moles of Cu by the volume of the solution.
Cu concentration (M) = Moles of Cu / Volume of solution (L)
= Moles of Cu / 0.100 L
4. Convert the concentration of Cu from moles per liter (M) to ppm:
- Since 1 ppm is equivalent to 1 mg/L, you can convert the concentration of Cu from M to ppm by multiplying by the molar mass of Cu (63.55 g/mol) and 1000.
Cu concentration (ppm) = Cu concentration (M) * Molar mass of Cu * 1000
By following these steps, you will be able to calculate the ppm of Cu in the given solution.