Question

A Fatty Acid Monolayer Calculations

The number of drops per mL (drops/mL) can be calculated from thre measured number of drops per gram of Hexane (drops/g), using the density of Hexane (0.659 g/mL) as a conversion factor from grams to mL. Calculate this using the following information.

Area(A)=1.227*10^16

Concentration of Stearic Acid/Hexane Solution: 7.01* 10^-5

Mass of weighing bottle with lid= 18.028g Mass of weighing bottle, lid and solution= 18.463 Solution Mass: 0.435

I'm getting mL per drop, and can't figure out how to get back to drops per mL.

Answer 1

solution mass = .435 g

conc = 7.01 * 10^-5 M

this means 1 liter sol contain

7.01*10^-5 * 86 = .006 g

so density of solution = 1gm/cm^3 because of very low conc of hexane

so .432 g = .435 ml solution

so you get .435 ml per drop

so 1 drop = 1/.435 ml = 2.26 ml