How do you prepare a solution of 12 M HCl and want to prepare 500 mL of a 0.4 M solution. Assume you have a 500-mL volumetric flask
I don't think your question is worded properly. I think you have 12 M HCl and want to prepare 500 mL of 0.4M.
c1v1 = c2v2
12*mL = 0.4*500
Solve for mL of the 12 M material. Place that in the 500 mL volumetric flask and make to the mark. Shake thoroughly.
To prepare a 500 mL solution of 0.4 M HCl from a stock solution of 12 M HCl, you will need to dilute the stock solution using a volumetric flask. Here's how you can do it:
1. Calculate the volume of the stock solution needed:
- Use the formula C1V1 = C2V2, where C1 is the concentration of the stock solution, V1 is the volume of the stock solution needed, C2 is the desired concentration, and V2 is the final volume of the solution.
- In this case, C1 = 12 M, V1 is unknown, C2 = 0.4 M, and V2 = 500 mL.
- Substitute the given values into the formula to get: 12 M x V1 = 0.4 M x 500 mL.
2. Solve for V1 (the volume of stock solution):
- Rearrange the equation to get V1 = (0.4 M x 500 mL) / 12 M.
- Solve the equation to obtain the required volume of the stock solution.
3. Transfer the calculated volume of the stock solution into the volumetric flask:
- Use a clean and dry pipette or volumetric flask to accurately measure the volume obtained in step 2.
4. Add distilled water to the volumetric flask:
- Fill the remaining volume (500 mL) of the volumetric flask with distilled water.
- Hold the flask at eye level and carefully add distilled water until the bottom of the meniscus aligns with the etched line on the neck of the flask.
5. Mix the solution:
- Stopper the volumetric flask and gently invert it several times to ensure thorough mixing.
You have now prepared a 500 mL solution of 0.4 M HCl using the 12 M stock solution. Remember to handle concentrated solutions like 12 M HCl with caution, as they can be corrosive and harmful.