A solution contains 500 g water and 34.2 g sucrose. What is the approximate mole fraction of sucrose?
Answer and explanation
Correct answer: 0.0036
Mole fraction requires moles of each component, not their masses directly. Sucrose moles = 34.2/342 = 0.100 mol. Water moles = 500/18 ≈ 27.78 mol. Total moles = 27.78 + 0.100 = 27.88 mol. Thus sucrose mole fraction = 0.100/27.88 ≈ 0.0036, so option A is correct. Using the mass ratio or forgetting water in the denominator would give the larger distractor values.
Frequently asked questions
What is the correct answer to this question?
0.0036
Why is this the correct answer?
Mole fraction requires moles of each component, not their masses directly. Sucrose moles = 34.2/342 = 0.100 mol. Water moles = 500/18 ≈ 27.78 mol. Total moles = 27.78 + 0.100 = 27.88 mol. Thus sucrose mole fraction = 0.100/27.88 ≈ 0.0036, so option A is correct. Using the mass ratio or forgetting water in the denominator would give the larger distractor values.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Some Basic Concepts of Chemistry. Topic: Mole concept and molar mass.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesWrite a review / Rate this question
Student Reviews
No published reviews yet.
