The concentration of a substance can be expressed using molarity, molality or percent.
<h3>What is concentration?</h3>
The term concentration has to do with the amount of substance present in solution. Now let us solve the problems individually;
a) Number of moles = 0.850 grams/80 g/mol = 0.011 moles
molarity = 0.011 moles/345 * 10^-3 L = 0.032 M
b) Number of moles = 13.5g /58 g/mol = 0.23 moles
molality = 0.23 moles/250 * 10^-3 Kg = 0.92 m
c) Number of moles = 16.5 g/128 g/mol = 0.13 moles
molality = 0.13 moles/54.3 * 10^-3 Kg =2.39 m
d) Total mass present = 12 g + 18 g + 25 g + 500 g = 555 g
mass percent of calcium sulfate = 12 g/555 g * 100/1 = 2.2 %
mass percent of sodium nitrate = 18 g/ 555 g * 100/1 = 3.2 %
mass percent of potassium chloride = 25 g / 555 g * 100/1 = 4.5%
mass percent of water = 500 g / 555 g * 100/1 =90.1%
e) Total mass present = 125 g + 1500g = 1625 g
Mass percent of NaCl = 125 g/1625 g * 100/1 = 7.7%
f) Total volume of solution = 15 L + 28 L = 43 L
percent by volume of acetone = 15 L/43 L * 100/1 = 34.9%
Learn more about concentration: brainly.com/question/10725862?
