You have the following stock solutions and solid chemicals in your lab:

1.5M NaCL
0.2M Tris buffer, pH 8.0
10 mg/ml Bovine serum albumin (BSA)
MgCl2 (solid, anhydrous) MW = 95.211 g/mole (95% pure)

How would you make 250 ml of the following solution???

0.2M NaCl
0.05M Tris, pH 8.0
0.25 mg/ml BSA
25mM MgCl2

If i understand the NaCL can be determined by c1v1=c2v2 but the BSA MgCL2 and Tris I don't understand, plus is the total suppossed to add to be 250 ml?

NaCl, BSA, and Tris are dilutions that use c1v1 = c2v2. There is no difference in the procedure for Tris and NaCl.

For BSA solution, you have a concn for that which isn't M but mg/mL. Same process.

The MgCl2 is not a dilution problem, per se, but it is diluted in the end.
For the MgCl2 find grams (or milligrams) MgCl2 required to make 250 mL of 25 mM MgCl2, from mols = M x L. You know M and L, solve for mols. Then mols = grams/molar mass. You know molar mass and mols, solve for grams. Then since the stuff is only 95% pure, divide that number by 0.95.
I'm not sure what total you are talking about for 250 mL. The FINAL solution must be 250 mL. The way you do that is to put grams/mL of the stock solution into a 250 mL volumetric flask and make to the mark with DI or distilled H2O. That way the final solution will ber 250 mL.

To make 250 ml of each of the desired solutions, you would need the following steps:

1. Calculate the amount of each reagent needed for 250 ml of solution.
- For NaCl:
- Given: Stock concentration = 1.5 M
- Desired concentration = 0.2 M
- Using the dilution formula (C1V1 = C2V2), you can determine the volume of stock solution needed as follows:
- C1 = 1.5 M, V1 (unknown), C2 = 0.2 M, V2 = 250 ml
- Rearranging the formula, V1 = (C2 * V2) / C1
- Substitute the values and calculate V1

- For Tris buffer:
- Given: Stock concentration = 0.2 M
- Desired concentration = 0.05 M
- Using the dilution formula (C1V1 = C2V2), you can determine the volume of stock solution needed as follows:
- C1 = 0.2 M, V1 (unknown), C2 = 0.05 M, V2 = 250 ml
- Rearranging the formula, V1 = (C2 * V2) / C1
- Substitute the values and calculate V1

- For BSA:
- Given: Stock concentration = 10 mg/ml
- Desired concentration = 0.25 mg/ml
- Since the desired concentration is lower than the stock concentration, you will need to dilute the stock solution. You can use the dilution formula (C1V1 = C2V2) to determine the final volume and concentration of the diluted solution:
- C1 = 10 mg/ml, V1 = (unknown), C2 = 0.25 mg/ml, V2 = 250 ml
- Rearranging the formula, V1 = (C2 * V2) / C1
- Substitute the values and calculate V1

- For MgCl2:
- Given: Molecular weight = 95.211 g/mol, Purity = 95%
- Desired concentration = 25 mM
- To calculate the mass of MgCl2 needed, you can use the following formula:
- Mass = (Desired concentration * Molar weight * Volume) / Purity
- Substitute the values (desired concentration, molar weight, volume, and purity) and calculate the mass needed.

2. Once you have calculated the volumes and mass of each reagent, you can proceed with the preparation of the solutions:

- For 0.2 M NaCl:
- Measure the calculated volume of 1.5 M NaCl solution and transfer it to a container.
- Add distilled water to bring the total volume of the solution to 250 ml.

- For 0.05 M Tris buffer, pH 8.0:
- Measure the calculated volume of 0.2 M Tris buffer solution and transfer it to a container.
- Adjust the pH of the solution to 8.0 using a pH meter or pH indicator and appropriate acidic/basic reagents if needed.
- Add distilled water to bring the total volume of the solution to 250 ml.

- For 0.25 mg/ml BSA:
- Dilute the calculated volume of the 10 mg/ml BSA stock solution with the appropriate amount of distilled water to reach a final volume of 250 ml.

- For 25 mM MgCl2:
- Measure the calculated mass of MgCl2 and dissolve it in distilled water to make a solution with a volume of 250 ml.

3. Finally, ensure that each prepared solution is thoroughly homogenized by mixing or shaking before use.

The total volume of the prepared solutions, if you follow the above steps, should add up to 250 ml.