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#1
02-03-2004, 06:42 PM
 ltfire Guest Join Date: Dec 2002 Location: E 161 St. and River Ave. Posts: 1,765
Convert solid to liquid

If you have a pill, or a capsule, that is labeled 20 Mg. , and you have the exact same ingredient in liquid form, how much of the liquid form need be drawn into an eye dropper to equal 20 Mg.?
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#2
02-03-2004, 06:49 PM
 friedo Guest Join Date: May 2000 Location: Brooklyn Posts: 23,653
That depends on the density of the substance, and how much other stuff is mixed in with the liquid.
#3
02-03-2004, 06:53 PM
 Exapno Mapcase Charter Member Join Date: Mar 2002 Location: NY but not NYC Posts: 29,704
20 mg of water is equal to 20 cc of water.

You would have to know the density of the other substance compared to water to be able to answer your question.

However, if you are talking about an actual pill or capsule, a medicine that contains 20 mg of the active ingredient, there is no way to answer this question without knowing the exact composition of the original. All medications have inactive ingredients mixed in with them, to help them dissolve, absorb, or simply to bulk them out to a large enough size to put a name or number or them.

And the liquid versions of these medications will likely have a different composition, different inactive ingredients, and possibly a different form of the medicine itself. There is usually no way to simply take a pill and dissolve it in water to make a match.
#4
02-03-2004, 06:54 PM
 Squink Guest Join Date: Oct 2000 Location: Yes Posts: 20,327
Or if you are asking about the liquid vs the solid form of the same substance, the answer would depend on how the density changes between solid and liquid. The solid is usually denser, but, as water as with water/ice, that's not always true.
#5
02-03-2004, 07:03 PM
 Bippy the Beardless Guest Join Date: Mar 2002 Location: Chili-con-valley Posts: 8,506
Well the pill capsule labelled 20 mg contains 20 mg of the active ingredient. You would have to weigh the pill/ capsule to get the mass of active plus inactive ingredient in it. Then if you know that the liquid form has exactly the same ingredients (how come it's liquid then? presumably they are at the same temperature/pressure) you need to measure the same mass of liquid as the mass of the capsule/pill. To do this with a pipette that measures volume you will need to know the density of the liquid form of the drug. Then you have the equation

mass of capsule = density of liquid x volume of liquid

will allow you to work out the unknown volume of liquid that is required.
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#6
02-03-2004, 07:29 PM
 Qadgop the Mercotan Charter Member Join Date: Apr 2000 Location: Slithering on the hull Posts: 25,977
Just call your pharmacist and ask how much of the liquid to take!
#7
02-03-2004, 09:26 PM
 scr4 Member Join Date: Aug 1999 Location: Alabama Posts: 14,232
Quote:
 Originally Posted by Exapno Mapcase 20 mg of water is equal to 20 cc of water.
No, 1mg is 1/1000 g, and 1g of water is 1ml=1cc. 20 mg of water is 0.02 cc.

Not that it matters to the OP since, as pointed out, 20mg refers to the amount of active ingredient. We don't know the concentration of the solid and liquid form of the medicine so we can't answer the question.

Nitpick: it's "mg" not "Mg". Small m means 1/1000, and capital M means 1000. 1 Mg would be 1 ton.
#8
02-04-2004, 11:06 AM
 Bippy the Beardless Guest Join Date: Mar 2002 Location: Chili-con-valley Posts: 8,506
Nitnitpick M = 1000000
#9
02-04-2004, 11:35 AM
 venterap Guest Join Date: Jul 2003 Location: Pretoria, South Africa Posts: 49
Quote:
 Originally Posted by Exapno Mapcase 20 mg of water is equal to 20 cc of water.
Err.. not quite: 1000cc = 1liter; 1liter of water has a mass of 1kg = 1000g
therefore 1cc has a mass of 1g
and 20mg = 20/1000 = 0.02 cc, or very little indeed
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#10
02-04-2004, 11:44 AM
 venterap Guest Join Date: Jul 2003 Location: Pretoria, South Africa Posts: 49
Quote:
 Originally Posted by scr4 No, 1mg is 1/1000 g, and 1g of water is 1ml=1cc. 20 mg of water is 0.02 cc. Not that it matters to the OP since, as pointed out, 20mg refers to the amount of active ingredient. We don't know the concentration of the solid and liquid form of the medicine so we can't answer the question. Nitpick: it's "mg" not "Mg". Small m means 1/1000, and capital M means 1000. 1 Mg would be 1 ton.
Oops, didnṫ see your post before I replied to the 20mg=2cc.

[nitpick of a nitpick]That would be one metric ton which is happily also about equal to a "long" ton (2200 pounds). Or does "ton" imply "metric ton"? What is a "tonne" then?[/nitpick of a nitpick]
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