A metalloid is an element that has properties that are intermediate between those of metals and nonmetals. Metalloids can also be called semimetals. On the periodic table, the elements colored yellow, which generally border the stair-step line, are considered to be metalloids.
a) Volume percent
Formula: % v/v = [volume solute / volume solution] * 100
Just to make it easy take a base of 50 volume parts of ethylen glycol and 50 volume parts of water to make 100 volumes of mixture (this assumpion will be valid for all the questions):
% v/v =[ 50 ml ethyleneglycol] / [100 ml mixture] * 100 = 50%
Answer: 50% v/v
b) Mass percent
% m/m = [mass ethylene glycol / mass solution] * 100
mass ethylene glycol = 50 ml * 1.114 g/ ml = 55.7 g
mass of mixture = 100 ml * 1.07 g/ml = 107 g
% m/m = [55.7 / 107 g] * 100 = 52.06 %
Answer: 52.06%
c) Molarity
M = number of moles of solute / liters of solution
number of moles of solute = mass in grams / molar mass
number of moles of ehtylene glycol = 55.7 g / 62.07 g/mol = 0.8974 mol
liters of solution = 0.1 liter
M = 0.8974 mol / 0.1 liter = 8.974 M
Answer: 8.974 M
d) Molality
m = number of moles of solute / kg of solvent
number of moles of ethylen glycol = 0.8974 mol
mass of water = 50 ml * 1 g/ml = 50 g = 0.05 kg
m = 0.8974 mol / 0.05 kg = 17.95 m
Answer: 17.95 m
e) mole fraction
mole fraction = [number of moles of solute] / [number of moles of mixture] * 100
number of moles of ethylen glycol = 0.8974 mol
number of moles of water = 50 g / 18.01 g /mol = 2.776 mol
mole fraction = 0.8974 mol / [0.8974 mol + 2.776 mol] = 0.244
Answer: 0.244
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