Topics: Mole, Water, Chemistry Pages: 1 (264 words) Published: July 9, 2011
Worksheet for determination of Avogadro’s Number
Trial 1Trial 2
Number of drops per mL from pipet46 drops50 drops
Average number of drops per ml48 drops
Vol. per drops of ethanol0.02 mL
Vol. of oleic acid per drop of ethanol solution0.0001 mL
Density of oleic acid0.895 g/cm^3
Grams of oleic acidM= D x V
M= 0.0179 g
Grams of oleic acid per drop of ethanol solutionM= D x V
8.95*10^-5 g

Diameter of circle formed:
Circle A1.5 cm1.1 cm1.7 cm
Circle B1.2 cm1.1 cm0.9 cm
Circle C0.6 cm0.8 cm1.0 cm

Average circle diameter1.1 cm
Vol. of oleic acid monolayer1x10^-4 mL
Estimated height of oleic acid monolayer1.05x10^-4 cm

Area of circle of oleic acid monolayer0.95 cm²
Surface area of top of one molecule2.1 x 10 cm²

Number of molecules per circle4.52x10^15 molecules
Grams of oleic acid per drop of ethanol sol8.95x10^-5 g

Molar mass of oleic acid282.52 g/mol
Number of molecule per gram of oleic acid5.05x10^19 molecule/g Number of molecules per mole of oleic acid1.43x10^22 molecule/mol Avogadro’s number6.022 * 10^23 unit/mol
Percent Error= {[6.022 x 10 units/mol – 1.43 x 10^22 molecules/g]/ [ 6.022 x 10 units/mol]} x 100 = 97.6 %