Describe how one would prepare these solutions in the laboratory, using weights reagents and volumes of solutions:

-500 mL of .100M K2Cr)4 stock solution from pure K2CrO4(s)

-10mL of .0025M K2CrO4(aq) from .100M K2CrO4(aq)

-What would the concentrations of FeSO4 and KCL be if 250mL of .350M FeSO4 were mixed with 150mL of .200M KCL? They do not react.

How many mols of the stock solution do you want? That's M x L = 0.500 x 0.100 K2CrO4 = ?

For the 0.0025 M solution use the dilution formula.
mL1 x M1 = mL2 x M2
10 mL x 0.0025 = mL2 x 0.100M
Solve for mL2, pipet that volume and make to 10 mL.

Assuming the volumes add, the total volume will be 250 mL + 150 mL = 400 mL. So the FeSO4 has been diluted from 250 to 400 so the (FeSO4) = 0.350 x 250/400 = ?
(KCl) = 0.200M x 150/400 = ?

To prepare these solutions in the laboratory, you will need to follow specific steps and measurements. Here's how you can prepare each of the solutions:

1. Preparing 500 mL of 0.100 M K2CrO4 stock solution from pure K2CrO4(s):
- We need to calculate the amount of K2CrO4(s) required using the molarity and volume of the desired solution.
- The equation for molarity is Molarity (M) = Moles (mol) / Volume (L).
- Rearranging the equation gives Moles (mol) = Molarity (M) x Volume (L).
- Substitute the known values: Molarity = 0.100 M and Volume = 0.500 L.
- Solve for Moles (mol).
- Now, you need the molar mass of K2CrO4. The atomic mass of K is 39.098 g/mol, Cr is 52.00 g/mol, and O is 16.00 g/mol.
- Calculate the molar mass of K2CrO4, which is (2 x 39.098 g/mol) + 52.00 g/mol + (4 x 16.00 g/mol).
- Multiply the calculated molar mass by the number of moles obtained earlier to get the mass of K2CrO4(s) required.
- So, you weigh the appropriate amount of K2CrO4 and transfer it to a container.
- Then, add distilled water and stir to make sure it is completely dissolved.
- Finally, adjust the final volume to 500 mL using a volumetric flask by adding more distilled water.

2. Preparing 10 mL of 0.0025 M K2CrO4(aq) from 0.100 M K2CrO4(aq):
- The same steps as above can be followed to calculate the amount of K2CrO4(aq) required in this case.
- The equation for molarity stays the same: Molarity (M) = Moles (mol) / Volume (L).
- Rearrange the equation to solve for Moles (mol), substitute the known values: Molarity = 0.0025 M and Volume = 0.010 L.
- Once you have the moles calculated, use the equation Moles (mol) = Molarity (M) x Volume (L) to determine the volume of the 0.100 M K2CrO4(aq) required.
- So, measure out the appropriate volume of the 0.100 M K2CrO4(aq) using a pipette or burette.
- Transfer it to a container, and then adjust the final volume to 10 mL using a volumetric flask by adding distilled water.

3. Finding the concentrations of FeSO4 and KCl after mixing:
- Since FeSO4 and KCl do not react, their concentrations in the mixed solution remain the same as the initial concentrations.
- Therefore, the concentration of FeSO4 in the mixture would still be 0.350 M.
- Similarly, the concentration of KCl in the mixture would still be 0.200 M.

Remember, always exercise caution and follow proper laboratory protocols when handling chemicals and equipment.