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If I reconstitute a 20 mg vial with 1.5 mL of bacteriostatic water, what concentration do I end up with?

Asked 28 Dec 2025Modified 7 months agoViewed 4.6k times
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What I am working with: 20 mg · 1.5 mL · bacteriostatic water.

I have worked this out and I would like someone to find the error, because I suspect there is one.

My working so far, for the record, is below, and I am fairly sure the error is in the unit conversion rather than the algebra.

Is my approach right even if my number is wrong?

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askedpriya_menon11k1528 Dec 2025
I tested this on two lots and got the same answer, so at least it reproduces. – plate_count_9k 4 months ago
The timing signature is the useful part. Everything else is confounded. – Dr_Otto_Lindqvist 3 months ago
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