Chemistry Assignment: Solving Mass% and Density Problems

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To solve the chemistry assignment, the mass percentage of sodium chloride can be calculated using the formula: mass% = (mass of NaCl / total mass) x 100, where total mass is the sum of the mass of NaCl and water. For the density calculation, the formula density = mass/volume applies, and the mass of the solution is given as 11.833g for a volume of 11.72ml. It's important to understand the conversion between different density units, such as grams per milliliter and kilograms per liter. The discussion emphasizes the need to correctly convert and apply units in these calculations. Mastering these concepts is essential for accurately solving the assignment problems.
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I have a chemistry assignment question that I don't understand. Any help you could give me as ot solving this problem would be greatly appreciated. Here is the question:
Suppose you make a solution that contains 10.23g of sodium chloride and 629g of water
a)what is the mass%of sodium chloride
b)If 11.72ml of your solution weighs 11.833g what is the density.

I should know how to do this problem but I havent' taken chemistry for 2 years
 
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Mass % = mass of consituent (in this case NaCl) / total mass x 100.

Total mass = mass NaCl + mass water.


Density = mass / vol.

Units of density could be kg/l (l = liter), kg/m3, g/cc (cc = cm3), or g/ml, as well as others.
 
I understand A but I still don't understand how to do B
 
ro=M/V
density = Mass/Volume

you have mass..now you need volume..as in astronuc posts there can be many density units.
there is a conversion from milliliter to gram or kg. So you got to find out how to do that conversion...simple steps of changing the metric/measurement unit..
like a conversion from yards to m.
 
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