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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: light on August 17, 2004, 12:05:28 AM

Title: 20 mg%
Post by: light on August 17, 2004, 12:05:28 AM

Calcium chloride (MW 110.99)

20 mg%

hello,

can anyone tell me how to make a 20mg% solution of calcium chloride? what makes me confused is the unit mg%. what on earth does it mean?

thanks!

Title: Re:20 mg%
Post by: Mitch on August 17, 2004, 02:29:37 AM

by weight?

Title: Re:20 mg%
Post by: light on August 17, 2004, 08:23:08 AM

here is an example i found;

Dinitrophenol (DNP - MW 184.11)

18.4 mg% - Dissolve 18.4 mg of 2,4-dinitrophenol to a final volume of 100 mL with water or buffer.

but what exactly does mg% mean?

Title: Re:20 mg%
Post by: Demotivator on August 17, 2004, 09:14:31 AM

It's a term I haven't heard before either, but I deduce that mg% = % by weight x 1000 (thus the term milli). In the DNP example, 18.4 mg = .0184 g.
(.0184g/100g total) x 100 = .0184% ..the actual percent.
.0184% x 1000 mg = 18.4 mg%

Title: Re:20 mg%
Post by: AWK on August 18, 2004, 04:14:42 AM

mg% - this term is used often in pharmacy and means - number of mg of solute in 100 g of solution.

Title: Re:20 mg%
Post by: thallium chick on August 18, 2004, 12:41:21 PM

doesnt mg mean miligram????

like maybe 20percent of a miligram??? im not a big fan of the metric system

Title: Re:20 mg%
Post by: Mitch on August 18, 2004, 05:57:18 PM

Quote from: th@llium_<hi<k on August 18, 2004, 12:41:21 PM

doesnt mg mean miligram????

like maybe 20percent of a miligram??? im not a big fan of the metric system

I would trust Awk

Title: Re:20 mg%
Post by: jdurg on August 18, 2004, 10:04:14 PM

mg% = mg/dL.  Trust me on this one.  I work with lab data all the time, so I constantly see this abbreviation used.  

Title: Re:20 mg%
Post by: AWK on August 20, 2004, 01:04:12 AM

Yes, mg means miligrams

100 grams and 1 dL for diluted water solution (eg physiological fluids) are apparently the same,
so Jdurg is also right (in fact for liquids a volume is used, but for solids - always mass).

Frankly saing, Light asked for calcium chloride solution, so Jdurg is slightly more right than me.

Mitch,  thank you to my fan.
.