Question #37d0d

1 Answer
May 2, 2017

The molarity of the glucose solution is ~~0.6color(white)(.)"mol/L".

Another way to say this is that it is a "0.6 molar" glucose solution.

Using the symbol for molarity, "M", you can write "0.6 M".

Explanation:

Convert given mass of glucose to mol glucose.

Multiply the given mass by the reciprocal of the molar mass.

3color(red)cancel(color(black)("g C"_6"H"_12"O"_6))xx(1"mol C"_6"H"_12"O"_6)/(180color(red)cancel(color(black)("g C"_6"H"_12"O"_6)))="0.017 mol C"_6"H"_12"O"_6"

Determine the volume of the water in liters (L).

Use the density formula to determine the volume of the water.

The density of water is 1.00"g/mL" to three significant figures.

"density"="mass"/"volume"

Solve for volume.

"volume"="mass"/"density"

"volume"=(30color(red)cancel(color(black)("g H"_2"O")))/((1.00color(red)cancel(color(black)("g H"_2"O")))/(1"mL H"_2"O"))="30 mL H"_2"O"

Convert "30 mL H"_2"O" to liters.

"1 L=1000 mL"

30color(red)cancel(color(black)("mL H"_2"O"))xx(1"L H"_2"O")/(1000color(red)cancel(color(black)("mL H"_2"O")))="0.03 L H"_2"O"

Determine molarity.

Molarity, "M", is "moles of solute"/"liters of solution", or "mol/L".

Divide the mol glucose by the volume of the solution in liters.

"M"=(0.017"mol C"_6"H"_12"O"_6)/(0.03"L")="0.6 mol/L C"_6"H"_12"O"_6 (rounded to one significant figure due to "3 g" and "30 mL")