Question

A solution is obtained by mixing 300 g of 25% solution and 400 g of 40% solution by mass. Calculate the mass percentage of the resulting solution

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Answer 1

Solution:-

As per the given question ,

• Mass of solution 1 (S 1) = 300 g

• Mass of solution 2(S 2) = 400 g

Mass of the entire solution

➸ S = S 1 + S 2

➸ S = 300 + 400 g

➸ S = 700 g

As per the formula ,

➸ %M/M = M 1 x 100/ S 1

here ,

• M 1 = mass of solute 1

• S 1 = Mass of solution 1

• S 1 = Mass of solution 2

On rearranging ,

➸ M 1 = % M/M x S 1 / 100

➸ M 1 = 25 x 300 / 100

➸ M 1 = 75 g

Similarly ,

➸ %M'/M' = M 2 x 100/ S 2

On rearranging ,

➸ M 2 = % M/M x S 1 / 100

➸ M 2 = 40 x 400 / 100

➸ M 2 = 160 g

Total mass of the solute

➸ M = M 1 + M 2

➸ M = 75 + 160

➸ M = 235 g

Mass percentage of the resulting solution ,

➸ %M /M = M /S

➸ % M /M = 235x 100 / 700

➸ %M/M = 33.57%

The mass percentage of the resulting solution is 33.57 %