If I have 500ml 65% A and a 100ml 82% A

How do we prepare 140ml 76% of A by mixing both the above solutions?

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If I have 500ml 65% A and a 100ml 82% A

How do we prepare 140ml 76% of A by mixing both the above solutions?

How do we prepare 140ml 76% of A by mixing both the above solutions?

- gene26
- Prolific Post-Master
**Posts:**138**Joined:**Jul 01 2012 10:14 pm

Just remember that N1xV1 = N2xV2, where N can be percentage, molarity or normality; V is the volume.

Assuming X ml of the 82% is needed to mix with (140-X) ml of the 65%,

X.82 + (140-X).65 = 140 .76

Solve for X

Assuming X ml of the 82% is needed to mix with (140-X) ml of the 65%,

X.82 + (140-X).65 = 140 .76

Solve for X

Retired academic researcher. Mention of a specific product does not imply my endorsement of the product. No conflict of interest or guarantee to work on the advice given. Do as I say, not as I do. Not liable to the loss of your valuable samples.

- relaxin
- PI of Posters
**Posts:**7190**Joined:**Jan 11 2006 5:40 pm**Location:**Mauna Kea

relaxin wrote:Just remember that N1xV1 = N2xV2, where N can be percentage, molarity or normality; V is the volume.

I did try to apply N1V1=N2V2

N1 = X.82 + (140-X).65

N2= .76

V1= ?

V2=140

but I couldn't come up with a equation for N1this seems like a GRE math

when do we use N1/V1 = N2/V2

- gene26
- Prolific Post-Master
**Posts:**138**Joined:**Jul 01 2012 10:14 pm

Your N1 is wrong (N is for concentration only). Since there are two solutions with different percentage involved, the total sum of N1V1 of the two solutions will be equal to N2V2 of the final solution.

V1 has different values for each of the original solutions, the sum should be equal to V2.

V1 has different values for each of the original solutions, the sum should be equal to V2.

Retired academic researcher. Mention of a specific product does not imply my endorsement of the product. No conflict of interest or guarantee to work on the advice given. Do as I say, not as I do. Not liable to the loss of your valuable samples.

- relaxin
- PI of Posters
**Posts:**7190**Joined:**Jan 11 2006 5:40 pm**Location:**Mauna Kea

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