CHE $1300$

Homework #$2$

I have a vitamin supplement which has $200mg$ of Vitamin A $($Chemical name: Retinol, formula $C_{20}{H}_{30}O)$ dissolved in $10$ milliliters of ethanol. What is the mass fraction of Vitamin $A$ in this supplement? What is the mole fraction of Vitamin A in the supplement?

I mix two fluids together, and I use the same mass of each fluid. They are completely miscible; in fact, the two chemicals are isomers. What is the composition of the mixture on a molar basis $($i$.$e$.,$ report as molar fraction of Chemical A$)?$ Give a numerical answer and a written explanation of how you arrived at it$,$ but do not use any equations.

Air is generally assumed to be $79\%$ nitrogen and $21\%$ oxygen on a volume basis. What is the composition of air on a molar basis? This problem is relatively trivial to solve if you look up a density for these gases. Don't. Instead, try starting with the ideal gas law....

I$\text{'}$m trying to mix up a drink for a party. It's a mixture of Guinness, which is $4\mathrm{.}3\%$ ethanol in water by volume, and Irish Whiskey, which is $80\%$ ethanol in water by volume. I want to combine these, and create a drink with is $16\%$ ethanol by volume. I also want one liter of this drink. Assume that the solutions will behave as ideal solutions, and determine the volume of Guinness and Irish Whiskey that I should combine, expressed in liters.