2 years ago

5. What is the mole fraction of NaOH in an aqueous solution that contains 31.0 % NaOH by mass?

Chemistry

1 answer:

Liono4ka [1.6K]2 years ago

6 0

Answer:

16.8%

Explanation:

31% NaOH molar mass 40 gm

69% H2O molar mass 18 gm

1000 gm would be

310 gm NaOH or 310/40 = 7.75 moles

690 gm of H2O or 690/18 = 38.333 moles

7.75 / (7.75 + 38.333) = .168 mole fraction

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