Question #71d05
1 Answer
Here's what I got.
Explanation:
Osmolarity is simply a measure of how many osmoles of solute you get in
Now, an osmole is simply
In order to find this solution's osmolarity, you must first find its molarity, which is defined as the number of moles of solute present in
Assuming that your glucose solution is
So, let's pick a
#3.8 color(red)(cancel(color(black)("g"))) * "1 mole glucose"/(180.16color(red)(cancel(color(black)("g")))) = "0.0211 moles glucose"#
Now, in order to find the number of moles present in
Let's say that the density of this solution is about
#100 color(red)(cancel(color(black)("g solution"))) * "1 mL solution"/(1.01color(red)(cancel(color(black)("g solution")))) = "99.01 mL"#
The number of moles of glucose present in
#1 color(red)(cancel(color(black)("L solution"))) * (10^3color(red)(cancel(color(black)("mL"))))/(1color(red)(cancel(color(black)("L")))) * "0.0211 moles glucose"/(99.01 color(red)(cancel(color(black)("mL solution")))) = "0.213 moles glucose"#
Since this is the number of moles of glucose present in
#"molarity = 0.213 mol L"^(-1)#
Now, glucose is a non-electrolyte, which means that it does not dissociate when dissolved in water.
Consequently, every mole of glucose dissolved in water will create
#"1 mole glucose = 1 osmole"#
Therefore, the osmolarity of this solution will be
#(0.213 color(red)(cancel(color(black)("moles glucose"))))/"1 L solution" * "1 osmole"/(1color(red)(cancel(color(black)("mole glucose")))) = color(darkgreen)(ul(color(black)("0.213 osmol L"^(-1))))#
I'll leave the answer rounded to three sig figs, but keep in mind that you only have one significant figure for the percent concentration of the solution.