describe how to prepare 500 ml of a 4.5 m solution of acetic acid from 1000.0 ml of a 14.1 stock solution. describe how a student would be able to make this solution. show all necessary calculations
I will assume you mean M and not m. M stands for molarity and m stands for molality. Also, I will assume that the 14.1 material is M since you did not show any unit.
mL1 x M1 = mL2 x M2
500 mL x 4.5M = mL2 x 14.1M
So mL2 = 500 x 4.5/14.1 = 159.57 mL
Add 159.57 mL of the 14.1 M stock solution (probably you would want to use a buret) to a 500 mL volumetric flask. I would add SOME distilled water to the 500 mL flask (say about 250 mL or so), swirl to mix, add water to the mark on the volumetric flask, stopper, mix thoroughly, label. Done.
Thank you so much!!
The work I did was correct then =}
I don't know about that since you chose not to show your work. If you had I could have checked it faster than working the problem myself.
To prepare a 500 ml solution of 4.5 M acetic acid from a 1000.0 ml stock solution of 14.1 M, you can follow the steps below:
1. Start by calculating the amount of acetic acid needed from the stock solution:
- The equation to calculate the amount of solute needed is:
Moles of solute needed = Molarity × Volume (in liters)
- Convert the volume from milliliters to liters by dividing by 1000:
Volume of stock solution (in liters) = 1000.0 ml ÷ 1000 = 1.0 L
- Substitute the values into the equation:
Moles of acetic acid needed = 4.5 M × 0.5 L = 2.25 moles
2. Calculate the volume of the stock solution required to obtain the desired amount of acetic acid:
- The equation to calculate the required volume is:
Volume of stock solution needed = Moles of solute needed ÷ Molarity of stock solution
- Substitute the values into the equation:
Volume of stock solution needed = 2.25 moles ÷ 14.1 M ≈ 0.16 L
3. Convert the volume of the stock solution needed from liters to milliliters:
- Multiply the volume by 1000:
Volume of stock solution needed (in ml) = 0.16 L × 1000 = 160 ml
4. Finally, add the calculated volume of the stock solution (160 ml) to enough water to make a total volume of 500 ml. Make sure to mix the solution well.
So, the student should measure 160 ml of the 14.1 M stock solution of acetic acid and add enough water to bring the total volume up to 500 ml.