Calculate the molarity of a solution of ethanol in water in which the mole fraction of ethanol is 0.040 (assume the density of water to be one).
Mole fraction of C2H5OH= .................1
Let the moles of C2H5OH= X
Now density of water = 1 (given)
And the weight of 1000ml of water = volume * density (from density = mass/volume)
= 1000 x 1=1000g
Therefore moles of water = 1000/18= 55.55 mol (18g is molecular mass of water)
Also mole fraction of C2H5OH= 0.040 (given)
Putting the values in equation 1,we get
=0.040=X/X+55.55
=0.040X+2.222 = X
OR X= 2.3145 mol
Molarity of solution = 2.314 M
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Calculate the the molarity solution of methanol in 1 litre offer water in which of the mole fraction of is 0.5
In this question water density given but still need to solve this question not have density of solution so a/c to my opinion that question fandamentically wrong. And if think water density is equal to solution density than answers will be2.01M
2.22/1.040=2.14461~2.1 Therefore,Molarity of Ethanol= 2.1M
WTF! 2.22÷1.040 = 2.134615~2.1M
write answer is 2.22
Volume of water i.e 1 litre is converted to 1000ml
Volume of water i.e 1 litre is converted to 1000ml
Why vol of water 1000 why God why
the answer is totally wrong,it should be 2.09 M
Thanks