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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: criticalerror on April 03, 2006, 10:03:09 PM

Title: Formula??
Post by: criticalerror on April 03, 2006, 10:03:09 PM

How many grams of KNO3 can be dissolved in 100 ml of H2O at 30 degrees?

iAt first i thought that i should use one of the molarity or molality formulas but i am just lost! Could some one please hint on what equation i should use in order to solve the problem above? i would really apreciate it!!

Title: Re:Formula??
Post by: mike on April 03, 2006, 10:24:50 PM

You need to look up the solubilty of KNO₃

Title: Re: Formula??
Post by: pink_ska_punk on April 11, 2006, 11:07:40 AM

this is only experimental data, but it might give you a clue. i found it on a coursework site when i was doing cw on potassium nitrate, it looks roughly right, just you need to match up columns with their headings.
Mass of potassium nitrate in the saturated solution /g   Volume of water in the saturated solution /cm³   Temperature of the saturated solution   Reciprocal of Kelvin temperature (1/T)/K-1   Solubility of potassium nitrate/mol dm-3 of water ?   Log 10 ?
      Celsius T/ºC   Kelvin T/K         
10.1   8.0   67º   340   1/340   12.5   1.09
10.1   10.0   57º   330   1/330   10   1
10.1   12.0   48º   321   1/321   8.33   0.92
10.1   14.0   42º   315   1/315   7.14   0.85
10.1   16.0   39º   312   1/312   6.25   0.79