How many molecules of water are in a kernel of popcorn?
Learning Objective: To determine the number of molecules of water lost by a popcorn
kernel.
Materials:
50 kernels
Flask tongs
Balance
250 mL Erlenmeyer flasks
weighing paper
Bunsen burner
ceramic tile
Procedure:
 Obtain 50 unpopped kernels of corn
 Mass all 50 and record in Data Table 1.
 Obtain 50 popped kernels of corn
 Mass all 50 popped kernels and record in Data Table 1.
** Carefully pop the kernels to prevent burning.
Data Table 1
Mass of 50 unpopped kernels
Mass of 50 popped kernels
Mass of water
(g)
(g)
(g)
Calculations:
1. Subtract the mass of the popped kernels from the mass of the unpopped kernels.
This will be the amount of water lost (in grams) during the experiment.
2. Divide the amount of water lost by 50 in order to find the average water lost for
each kernel.
3. Divide the grams of water lost per kernel by the molar mass of water (18 g/mole).
This will give you the number moles of water lost.
4. Multiply the moles of water lost for each kernel by Avogadro’s number. This will
be the number of molecules of water driven off during popping.