Why do cokes explode in the freezer?

Why do any glass bottles containing low or no alcohol explode when frozen?
Because when water freezes, it expands. "Bang!"  Not always; some
bottles may be strong enough to resist, or so shaped that the
expansion can occur without breaking the bottle.

Maybe when the coke freezes, some of the CO2 comes out of solution,
and increases the pressure in the can as well.  I'd need to look at
some data, like the temperature-solubility data for different phases
and how much free volume is in Coke cans.  That's way more than two
dollars of work.

Its all about pressure, the coke idea above is right, CO2 is forced
out by the freezing liquid. Same thing happens with the air although
ive never tried it. As for water and solutions containing high
concentrations of water its different ---- the bonding of he H-O-H
means that the two hydrogens are attracted to the other two of another
molecule creating a ring shape. This means that water expands (for
more info ask a geographer about frost shattering). This also means it
(ice, solid water) can float.