mg to mg/ml

[Unregistered]

I have 250mg of dry powder that I need to convert to a 10mg/ml solution. I was thinking since 10mg/ml is 1% I would add 25 ml of solvent. I am on the right track.

[Robert Fogt]

If you want 10 mg of powder per ml of solvent, then:

250 mg / 10 mg/ml = 25 ml

So you would need 25 ml of solvent.

You came up with the correct answer, but you came up with it in a weird way. 10 mg/ml is not 1%, and 1% of 250 is 2.5 not 25. But you ended up with a correct result so we overlook how you did it. :)

[Mrs X]

Also, if you need the resulting solution for analysis, you have to weigh the powder carefully, and you have to make the solution up in a volumetric flask. In this case, you need 25mL total, not 25mL solvent, + 250mg powder. You weigh the powder, you wash it into the flask with solvent, rinse out the weighing vessel several times, and add each rinse to the flask. Make sure all the powder is disolved (or at least properly dispersed if it doesn't disovle), then make up to the mark with solvent.

[Unregistered]

In defence of the the originator, and not wishing to undermine the administrator, my understanding is that 10mg/ml IS 1% (w/v) and 250mg is 1% of 25ml so I can understand how he came up with the answer, albeit I agree it is a weird way to do it.

[Unregistered]

10/1 = 10 not .01 or .1

[Unregistered]

10/1 = 10 Correct but its not 10/1 if ml were 1 then it would say 1 but its ml so there is something beyond they laymens brain here.

swim instinct says it isnt 1% but brain cant argue with it not being 1% till he put it all out here.

10 milligrams of X per Millilitre of Liquid
1000 milligrams of X per 100 millitres
10 000 milligrams of X per 1000 militres
10 grams per litre.
1 gram per 0.1 litre

Swim can see it now, 10mg of X per Millilitre is effectivellu

100mg per 10mls
1000mg per 100mls
10 000mg per litre
which is 10grams per litre
10/1000
1/100
0.01 x 100/1= 1%

Fare to tired atm to now requestion any logic issues.
i tried but brain hurts good night

[Unregistered]

I would like to know how to get the grams to ml in this formula (doxepin 33%, gabapentin 6%, lidocaine 5% in lipoderm cream) 60 grams or 1000 grams

[Unregistered]

if you have 20 mg strength powder and want to make a solution in a 30 mL bottle... how much powder do you use? is it 6.7 g? please advise... thanks!

[Unregistered]

.66mg/ml base on my computation, not g

[Unregistered]

I bring 600 ltrs diesel but it is calculate only 500 kgs. I want know specific convertion.

[JohnS]

I bring 600 ltrs diesel but it is calculate only 500 kgs. I want know specific convertion.

The density of diesel can vary lot to lot. For high precision, it should be measured for the lot in question. On average, it runs about 0.84 kg/L, so 600 L should be around 504 kg, so 500 kg seems reasonable (within range of variation).

[Unregistered]

Best way to calculate

vial contains 500mg/1ml

dose prescribed is 300mg

how much would you draw up

[Unregistered]

0.6ml or 3/5 of a ml

Best way to calculate

vial contains 500mg/1ml

dose prescribed is 300mg

how much would you draw up

[Unregistered]

How to 500 mg po qd x 30 days but on shelf i have 220mg/5ml 473. how many ml is required for one dose

[JohnS]

How to 500 mg po qd x 30 days but on shelf i have 220mg/5ml 473. how many ml is required for one dose

500 mg x 5 mL/220 mg = 11.4 mL

[Unregistered]

I am trying to figure out how many units to bill when we give a Depo-provera shot. The shot is 150 mg/mL and the billing unit is mg. Can anyone help?

[Unregistered]

morphine 20 mg/ml give 2 mg. How do I do the math?

[JohnS]

morphine 20 mg/ml give 2 mg. How do I do the math?

Divide by the concentration (invert and multiply)
2 mg x 1 mL/20 mg = 0.1 mL