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Molarity and Molality Problems


Asian

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Can someone please explain to me how to do this problem. The molarity and molality of potassium chloride solution are 1.000 mol/L and 0.9750 mol/kg. what is the solutions density? I got an answer of 1.101 g/ml. will someone show me how to do it and verify to see if my answers right?

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I dont see any problem...

 

Edit: When I worked the problem, I got 1.026 g/ml. I simply canceled out terms to find the density...

 

(1.00 mol KCl/ 1L) * ( 1 kg / 0.9750 mol KCl) * (1000 g/ 1 kg) * ( 1L / 1000 ml) = 1.026 g/ml

 

Are you sure there wasn't more to the problem?

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You must find out how to convert molarity to molality. Correct conversion formula will contain density and molar mass - you have to solve for density. Check out these concentration lectures for hints on converting (read about %ww to molarity conversions for general outline).

 

Strange thing is that 1.0000M solution of KCl is 1.0312 molal. Looks like the data in question are questionable.

 

Borek

--

Chemical calculators at www.chembuddy.com

concentration conversion calculator

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