no idea how to do this...
describe how you would prepare from the specified stock solution: 400 mL of 0.45 M urea starting with a 6 M urea stock solution
To prepare 400 mL of a 0.45 M urea solution from a 6 M urea stock solution, you need to calculate how much stock solution and solvent (water in this case) are required.
Here's the step-by-step process:
1. Determine the amount (volume) of the final solution:
- The volume required is 400 mL.
2. Determine the concentration of the stock solution:
- The stock solution concentration is given as 6 M.
3. Use the formula: C1V1 = C2V2 (where C1 and V1 are the initial concentration and volume, and C2 and V2 are the final concentration and volume).
- C1 (stock solution concentration) = 6 M
- V1 (volume of stock solution) = ? (unknown volume)
- C2 (desired concentration) = 0.45 M
- V2 (final volume) = 400 mL
4. Rearrange the formula to solve for V1:
V1 = (C2 * V2) / C1
(0.45 M * 400 mL) / 6 M
(0.45 * 400) / 6 = 30 mL
5. Measure 30 mL of the 6 M urea stock solution using a measuring cylinder or pipette.
6. Add the measured stock solution to a container (e.g., beaker or flask).
7. Fill the container with water up to the desired final volume (400 mL). You can use a graduated cylinder or volumetric flask to measure the water accurately.
8. Stir or swirl the solution gently to ensure proper mixing.
You have now prepared 400 mL of a 0.45 M urea solution from the 6 M urea stock solution.