Assume that you have 1,2,5,and 10 ml pipets and a 25mlvolumetric flask. Describe
ID: 690086 • Letter: A
Question
Assume that you have 1,2,5,and 10 ml pipets and a 25mlvolumetric flask. Describe in detail how you would prepare asolution with a concentration near 0.10 M from a 0.650 M stocksolution. Calculate the final concentration of the dilutedsolution( it won't be exactly 0.10 M). It should be within 10% of0.10 M. Any help would be appreciated Assume that you have 1,2,5,and 10 ml pipets and a 25mlvolumetric flask. Describe in detail how you would prepare asolution with a concentration near 0.10 M from a 0.650 M stocksolution. Calculate the final concentration of the dilutedsolution( it won't be exactly 0.10 M). It should be within 10% of0.10 M. Any help would be appreciatedExplanation / Answer
The next step is to find out how much stock would be neededfor a 25mL of 0.1M solution. (You need to find this out becauseyour flask can hold a MAXIMUM of 25 mL.) M1V1=M2V2 (0.65M)(x)=(0.1M)(25mL) x=3.84 mL
You can not accurately measure that amount, but you canaccurately measure out 3 mL using your 1 mL pipet.
Next step is to find out what the molarity of the solutionwould be if you used only 3mL. M1V1=M2V2 (0.65M)(3mL)=(x)(25mL) x= 0.078 M this number is not within the 10% range. (Thesolution has to be atleast 0.09M)
Since the greatest amount of stock solution you can use is 3mL, try changing the amount of new solution. You have to go lowerthe amount of water added to increase the concentration. Let's try20m! This number works because you have access to a 10mLpipet. M1V1=M2V2 (0.65M)(3mL)=(x)(20mL) x=0.0975M
How to prepare the solution: Measure out 3mL of the stock solution using the 1mL pipet, andplace it into the volumetric flask. Add 17mL of deionized water tothe volumetric flask using the various pipets. (You only add 17mLof DI water because the final solution is going to be 20 mL and 3mL is already there.) Then you cover the volumetric flask andinvert several times to mix the solution.
If you need any further help let me know :)