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To prepare a 200 mL of aqueous stock solution X, you transferred 50mL of a known

ID: 675808 • Letter: T

Question

To prepare a 200 mL of aqueous stock solution X, you transferred 50mL of a known concentration solution into a 200 mL volumetricflask. If you realize that the volumetric flask was contaminatedwith water droplets after you cleanly transferred the knownconcentration solution. The 200 mL solution X will have a
(higher, lower or same) concentration than(as) youoriginally calculated.
I could have sworn the answer was lower but I got it wrong...this was my reasoning:
M1V1=M2V2 assume the molarity of X is 1. (1)(.05)=(M2)(.2) ...M2=.25
So if there were extra water droplets in the vol flask, V2would be more than .2L, therefore you'd be dividing by a largernumber and M2 would be smaller. Where did I go wrong?
Also if I could get some help on this one...
You transfer a 2M stock solution of Y into a container using aslightly wet pipet containing water drops. The concentration of thetransferred solution Y has a

(lower,higher, or same) concentration than(as) 2M.

Thanks!
I could have sworn the answer was lower but I got it wrong...this was my reasoning:
M1V1=M2V2 assume the molarity of X is 1. (1)(.05)=(M2)(.2) ...M2=.25
So if there were extra water droplets in the vol flask, V2would be more than .2L, therefore you'd be dividing by a largernumber and M2 would be smaller. Where did I go wrong?
Also if I could get some help on this one...
You transfer a 2M stock solution of Y into a container using aslightly wet pipet containing water drops. The concentration of thetransferred solution Y has a

(lower,higher, or same) concentration than(as) 2M.

Thanks!

Explanation / Answer

For the first one water droplets will change the concentrationof a weak acid, but not the amount of moles present, which iswhat’s important in this case, so it stays the same. For the second, it's the same as well for the same reason asone. Good luck
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