Question 29

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).

Answer

Mole fraction of C_{2}H_{5}OH= .................1

Let the moles of C_{2}H_{5}OH= 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 C_{2}H_{5}OH= 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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The mass of an electron is 9.1 × 10

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Sameer
2019-07-02 20:02:19

Calculate the the molarity solution of methanol in 1 litre offer water in which of the mole fraction of is 0.5

Mukesh jain
2019-06-26 11:02:30

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

ISMAIL
2019-06-09 16:11:36

2.22/1.040=2.14461~2.1 Therefore,Molarity of Ethanol= 2.1M

ISMAIL
2019-06-09 16:09:14

WTF! 2.22Ã·1.040 = 2.134615~2.1M

sachin
2019-05-02 13:51:22

write answer is 2.22

Shanaya
2019-04-27 14:35:32

Volume of water i.e 1 litre is converted to 1000ml

Shanaya
2019-04-27 14:28:13

Volume of water i.e 1 litre is converted to 1000ml

Wajahat
2018-12-11 14:51:25

Why vol of water 1000 why God why

phd in chemistry
2018-11-12 21:56:10

the answer is totally wrong,it should be 2.09 M

Abhi
2018-09-15 08:44:05

Thanks

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