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  #1  
Old 02-03-2004, 06:42 PM
ltfire ltfire is offline
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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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Old 02-03-2004, 06:49 PM
friedo friedo is online now
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That depends on the density of the substance, and how much other stuff is mixed in with the liquid.
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Old 02-03-2004, 06:53 PM
Exapno Mapcase Exapno Mapcase is offline
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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.
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Old 02-03-2004, 06:54 PM
Squink Squink is offline
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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.
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Old 02-03-2004, 07:03 PM
Bippy the Beardless Bippy the Beardless is offline
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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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Old 02-03-2004, 07:29 PM
Qadgop the Mercotan Qadgop the Mercotan is offline
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Just call your pharmacist and ask how much of the liquid to take!
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  #7  
Old 02-03-2004, 09:26 PM
scr4 scr4 is online now
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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.
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Old 02-04-2004, 11:06 AM
Bippy the Beardless Bippy the Beardless is offline
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Nitnitpick M = 1000000
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Old 02-04-2004, 11:35 AM
venterap venterap is offline
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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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Old 02-04-2004, 11:44 AM
venterap venterap is offline
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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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