Composition of Mixtures Practice Test

A nonreacting mixture contains $1.0\text{ mol}$ of CH$_4$ and $4.0\text{ mol}$ of H$_2$. What is the mole fraction of CH$_4$ in the mixture?

A student makes a nonreacting solution by mixing $15.0\text{ g}$ of ethanol (C$_2$H$_5$OH) with $35.0\text{ g}$ of water. What is the mass percent of ethanol in the solution?