# Question #bbd91

##### 1 Answer

You need to know the identity of the solute.

#### Explanation:

You can't provide a numerical answer here because the problem doesn't provide the *identity* of the solute, which you need in order to convert its mass to **moles**.

I'm not really sure what you're supposed to solve for here, but I'll show you how to convert the given *mass by volume percent concentration*, **molarity**, **molar mass** equal to

So, in order to know the solution's **molarity**, you need to figure out how many moles of solute you have in

Its mass by volume percent concentration tells you that you get **for every** **of solution**.

This means that the sample we've picked will have a total mass of solute equal to

#1 color(red)(cancel(color(black)("L solution"))) * (10^3color(red)(cancel(color(black)("mL"))))/(1color(red)(cancel(color(black)("L")))) * "5.67 g solute"/(100color(red)(cancel(color(black)("mL solution")))) = "56.7 g solute"#

To convert this to **moles**, use the **molar mass** of the solute

#M_"M" color(white)(.)"g mol"^(-1) = (M_"M" color(white)(.)"g solute")/"1 mole solute"#

In your case, the sample will contain

#56.7 color(red)(cancel(color(black)("g solute"))) * "1 mole solute"/(M_"M" color(red)(cancel(color(black)("g solute")))) = (56.7/M_"M")" moles solute"#

Since this is the number of moles of solute present in **molarity** will be equal to

#color(darkgreen)(ul(color(black)(c_"5.67%" = (56.7/M_"M")color(white)(.)"mol L"^(-1))))#

Notice that you don't need to know the **density** of the solution in order to figure out its molarity, the mass by volume percent concentration is enough here.