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Since I've already done similar calculations on moles of salt,
sugar, water, and horses (yes, horses), I couldn't
pass up this latest twist, especially since it has some interesting
calculations and results. First, we need to know the volume of an
M&M™ candy (milk chocolate: no peanut, peanutbutter, or crispy): I
was going to figure this out myself by purchasing a bag of M&Ms from the
bookstore downstairs, and then measuring their displacement with a graduated
cylinder, but then I found Bernie Tao's "M&Ms contained in an Erlenmeyer Klein Flask"
site. According to Bernie Tao's calculations, the volume of a single
M&M candy is 0.45239 cc (cubic centimeters). While you weren't
originally
interested in the void volume of the M&Ms, he has already calculated
this for M&Ms packed in a Hexagonal Close Packed (HCP) arrangement
and determined this to be 40.31% of the total space; i.e., if the void
volume is 40.31%, then the M&Ms should take up 59.69% of the available
space. Next, we need the volume of Lake Erie - you gave a volume of 483
km^{3}, which exactly agrees with the Lake Erie Facts
and Figures pages. Now, on to the calculations:

483 km^{3}= 483 x 10^{9}m^{3}= 483 x 10^{15}ccDivided by the volume of an M&M adjusting for void volume, andIn HCP: 637 x 10^{15}M&Ms per Lake Erie (6.37 x 10^{17}) Compressed (i.e. no void volume): 1069 x 10^{15}M&Ms (1.07 x 10^{18}) 6.02 x 10^{23}/ 1.07 x 10^{18}= 5.63 x 10^{5}6.02 x 10^{23}/ 6.37 x 10^{17}= 9.45 x 10^{5}

So, if one were to simply empty Lake Erie of water, flora, and fauna, and
then fill it with M&Ms (don't eat the ones in the silt - yech!), it
would take **945,000 holes the size of Lake Erie to hold a "mole" of
M&Ms**, or one hole the size of
Lake Erie would contain 1.06 micromoles (µM) of M&Ms. (We use
micromolar concentrations a lot in the lab, so I'll have to remember this
one
for incoming students.) If, on the other hand, one were to first
purée the M&Ms and then fill an emptied Lake Erie, it would only
take
a measly 563,000 holes the size of Lake Erie to hold a mole of M&M
purée
(not as appetizing, but easier to walk across).

Since those are still some pretty large numbers, I decided to use what was
left of the mole of M&Ms after filling Lake Erie, and see what else I
could fill. None of the world's lakes were much better at holding a mole of
M&Ms, so I turned to the oceans. According to various sources, the volume of earth's
oceans is around 1.35 billion (thousand million)
km^{3}:

1.35 x 10^{9}km^{3}= 1.35 x 10^{24}cc in HCP: 1.78 x 10^{24}M&Ms to fill the world's oceans (I decided against the purée) 1.78 x 10^{24}/ 6.02 x 10^{23}= 2.96 Or, if you prefer:

(An equivalent amount of water would fill about two ounces - a quarter cup.)

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