0.1 mol glucose is dissolved in 90 g water. What is the mole fraction of water?
Answer and explanation
Correct answer: 0.980
The mole fraction of a component equals its moles divided by the total moles of all components. Water has molar mass 18 g mol⁻¹, so 90 g water contains 90 ÷ 18 = 5 mol. Total moles are 5 + 0.1 = 5.1 mol. Therefore, xwater = 5 ÷ 5.1 = 0.9804, approximately 0.980, making option C correct. The smaller complementary fraction would describe glucose, not water.
Frequently asked questions
What is the correct answer to this question?
0.980
Why is this the correct answer?
The mole fraction of a component equals its moles divided by the total moles of all components. Water has molar mass 18 g mol⁻¹, so 90 g water contains 90 ÷ 18 = 5 mol. Total moles are 5 + 0.1 = 5.1 mol. Therefore, xwater = 5 ÷ 5.1 = 0.9804, approximately 0.980, making option C correct. The smaller complementary fraction would describe glucose, not water.
Which subject and chapter does this question cover?
This is a Class 11 Chemistry question. Chapter: Chapter 01: Solutions.
