Author: Chris Morse
This puzzle is a standard empirical chemistry question from general
The Hydrogren and Carbon moles could be determined from the amounts
of carbon dioxide and water present.
The nitrogen could be found from the nitrogen dioxide gas and the
ideal gas law using 1 atm and 0 degrees celcius (STP).
To deterine the amounts of bromine and chlorine, a little algebra
needed to be done in order to separate out the mixture of the two
For the sulfur, the titration gave the proper moles of sulfur.
Finally, to find the oxygen, the only way is to subtract ALL the
masses of the previous 6 elements from the 5.11g total. Then this too
can be converted to moles.
The smallest ratio of all the moles gives this empirical formula:
C H Br Cl N O S
6 2 7 3 7 7 3
This is in the standard form... C then H then alphabetical by symbol.
Looking at the subscripts, this reads as a phone number 627-3773, my
office phone number at Tufts, where I teach chemistry.
If you listened to the voice mail, I told you the word ANACHRONISTIC.