Question

calculate the molality of 20% by weight potassium carbonate solution.​

Answer 1

Answer:

1.811

Explanation:

20% by weight (Or mass) means 20 g of K2CO3 in 100 g of solution.

=>Weight of solvent

= (weight of solution) - (weight of solute)

=>Weight of solvent= 100-20 =80 g= 0.08 kg

We know,

molality =(moles of solute) /(mass of

solvent in kg)

=>molar mass of K2CO3= 39*2 +12 +16*3

=> 138 amu

hence, molality= 20/(138×0.08)

=>20/11.04

=>molality=1.811

Hope it helps.

Please mark as Brainliest..

Answer 2

The molality of the solution is 1.75m

GIVEN

Mass% of Potassium carbonate = 20%

TO FIND

Molality of the solution.

SOLUTION

We can simply solve the above problem as follows;

It is given,

Mass% Of K₂CO₃ in the solution = 20%

This means in 100 grams of solution the weight of potassium carbonate = 20 grams

Mass of solvent = 100-20 = 80 grams.

We know that,

Molality = Moles of solute/Volume of solution in kg

Therefore,

Moles of K₂CO₃ = 20/138 = 0.14 moles

Mass of solvent = 80/1000 = 0.08 kg

Putting the values in the above formula we get;

m = 0.14/0.08 = 1.75 M

Hence, The molality of the solution is 1.75m

#Spj2