# Finding mole fraction from molarity and density

A solution of H2SO4 with concentration of 2,325 M at 15 °C has a density of 1,140 g/mL. Find the molar fraction.

I know what molar fraction is, but I really don't understand how to get it from the data I get. I tried calculating all other things like mass/mass ratio or molality and rearranging them to find some sort of relation between the data, but I couldn't find any way of solving for n(solution) or anything like that.

Am I missing something?

• Follow the steps to calculate molality, but calculate the amount of solvent instead of the mass of solvent.
– Karsten
Aug 29, 2022 at 14:41
• Write particularly what you have tried, as the calculation is very simple and it is difficult to miss it. Aug 30, 2022 at 2:57
• @Poutnik i don't remember exactly what i tried because i erased everything that didn't work from my document, to save space. i can say that i'm probably missing something because i'm pretty much new to the topic, so all i've tried so far is stringing all various data i had together to try and find an equation that would allow me to find the molar fraction without any unknown variable, or having them all cancel out, but i always get one or two. what is the calculation you're talking about?
– AGL
Aug 30, 2022 at 7:46
• My point was, for homework-like questions, it is expected to provide evidence of history of your effort to understand principles leading to the solution. No explicit effort looks exactly like no effort. Considering the fact the solution is very trivial..... Aug 30, 2022 at 7:51
• You already know H2SO4 molar amount in 1 L. From that you get its mass in 1 L. Density provides total mass of 1 L. Subtracting gets you the mass of water, from which you get water molar amount. You need molar masses of H2O and H2SO4 (approximate integers or precise from looking them up.) Aug 30, 2022 at 7:58