1.00 mL of a 0.0500 M sucrose solution is transferred to a 100 mL volumetric flask, and the flask brought up to volume. 5.00 mL are taken from the 100 mL volumetric flask and transferred to a 0.500 L flask, and it is brought up to volume. What is the resulting concentration of sucrose in the 0.500 L flask?
you diluted it by a factor of 100 (added 99 parts water). then, you diluted it another factor of 100 (.005L to .5L).
New concentration: .0500/1E6 M
i don't understand, can u explain using the
formula m1v1=m2v2?
Not with that formula.
oh, is there an easier way to this problem?
I erred. Goodness. You diluted it 100 times, then diluted it 100 times again.
new concentration=.05M/(100x100)=.05/10,000 or .05*10^-4 or 5*10^-6 M
If you want to do it by the m1v1 = m2v2 formula you can do it twice.
The first one is 1x.05 = 100*m
m = 0.05/100 = 5E-4
Then m1v1 = m2v2 the second time.
5E-4*5mL = 500mL x M
5E-4 x (5/500) = 5E-6M
If you insist on a formula that will do it; however, I like to do it this way.
0.05 M is what we start with. So
0.05M x (1/100) x (5/500) = %E-6M
oops. 5E-6
thanks drbob22, much better explanation!
ccny?
To find the resulting concentration of sucrose in the 0.500 L flask, we need to consider the dilution that occurs in each step.
Step 1: Dilution in the 100 mL volumetric flask.
Initially, we have 1.00 mL of a 0.0500 M sucrose solution in the 100 mL flask. By adding water to bring the volume up to 100 mL, we are diluting the solution. The number of moles of sucrose remains constant, but the volume increases.
To calculate the concentration after dilution, we can use the formula:
C1V1 = C2V2
Where:
C1 = initial concentration (0.0500 M)
V1 = initial volume (1.00 mL)
C2 = final concentration (unknown)
V2 = final volume (100 mL)
Rearranging the formula, we have:
C2 = (C1 × V1) / V2
C2 = (0.0500 M × 1.00 mL) / 100 mL
C2 = 0.0005 M
So, the concentration of sucrose after dilution in the 100 mL flask is 0.0005 M.
Step 2: Dilution in the 0.500 L flask.
Now, we have a 5.00 mL sample from the 100 mL flask, which contains the sucrose concentration of 0.0005 M. We transfer this sample to a 0.500 L flask and bring it up to volume.
Using the same formula as before:
C1V1 = C2V2
Where:
C1 = initial concentration (0.0005 M)
V1 = initial volume (5.00 mL)
C2 = final concentration (unknown)
V2 = final volume (0.500 L)
Rearranging the formula, we have:
C2 = (C1 × V1) / V2
C2 = (0.0005 M × 5.00 mL) / 0.500 L
C2 ≈ 0.005 M
Therefore, the resulting concentration of sucrose in the 0.500 L flask is approximately 0.005 M.