Question

Part A) Using your graduated cylinder, you calibrate the pipet you will be using and the values you collect are as follow. What is the average number of drops per mL of benzene.

  21 drops   

 20 drops   

  17 drops  

Answer: 19.3 drops

Part B) After calibration, you use the oleic acid/benzene solution to form a monolayer. It takes   8 drops   ,   9 drops    and   8 drops    before the layer on the water solution starts to make a bubble tha does not go into solution. What is the average number of drops for your monolayer?

Answer: 8.33 drops

Part C) Since we have the number of drops it takes to make a monolayer and we have the number of drops it takes to make one mL of benzene, we can determine the mL of oleic acid/benzene it takes to form a monolayer.  

Answer: 0.431 mL

Part D) Next we need to determine the mass of oleic acid in the monolayer. The concentration of the oleic acid/benzene solution is 0.02g/L. Calculate how many grams of oleic acid is in one drop.

Part E) sWith this information, we now need to calculate the volume in milliliters. We need to know how many mLs a drop of oleic acid occupies using the density of 0.895 g/mL and the number of drops of oleic acid solution used.

Part F) Determine the volume of the monolayer from the above information.

ANSWERS NEEDED FOR PARTS D, E, AND F

Answer 1

oleic acid/benzene solution is 0.02g/L

using the density of 0.895 g/mL

8.33drops/ mL
Take the inverse because you want ml/drops.
1/8.33= ml / drop = 0.12 ml per drop



0.12ml/drop = 0.00012 Liter/drop
multiple 0.02 g/Lby 0.00012 Liters/drop to get the units grams/drop
0.02 * 0.00012 grams/ drop
MW of oleic Acid = 2842grams/mol
Divide g/drop by grams/ mol to get the units mol/drop.