Name____________________________________Class_______Date______________
Molar Mass Lab
Part One:
Purpose: Determine the number of moles and particles in a substance.
*** PLEASE DO NOT EMPTY THE CONTENTS OF THE BAG OUT ONTO THE SCALES. AN EMPTY BAG HAS BEEN
PROVIDED SO THAT YOU CAN SUBSTRACT OUT THE MASS OF THE BAG FROM EACH SAMPLE.
Aluminum
Dextrose (C6H12O6)
Lead (II) Nitrate
Mass of Sample
Molar mass of
substance (show
work)
Moles of each
compound (show your
calculation and correct
unit on each answer)
Number of particles of
each substance (show
your calculation and
correct unit on each
answer)
Part Two:
Purpose: Determine the amount of paraffin that you used to color your picture.
Crayons are mostly paraffin wax, C25H22. When you color your picture with crayon you are leaving paraffin molecules
on the paper!
1. Weigh your crayon( most used) on the scale.
2. Color your picture ! Make it look nice !!!!
3. Reweigh your crayon once you coloring is completed.
Mass of crayon (before)
Mass of crayon (after)
Mass of crayon used
Calculations:
1.
What is the molar mass of paraffin?
2. How many moles of paraffin wax were used to color your picture?
3. How many individual atoms are used in your picture?
4. Another student did this lab but used chalk instead of crayon. The predominant substance in chalk is calcium
carbonate. If she used 1.2g of chalk to color her picture:
a. How many formula units of calcium carbonate did she use to color her picture?