Originally posted by not_important
Chlorine radical reactions are triggered by light in the 300 to 380 nm range, Pyrex and similar borosilicates transmit down 280 nm or so; there's no
need for quartz unless the reaction requires that extra energy in the radicals formed. BTW, bromine absorbs in the range 360 to 510 nm.
Some mercury vapour lamps include shunts within the outer bulb that will open if run in air. Also, if the design of the bulb places the phosphors on
the inner surface of the outer bulb; removing that bulb will given you lots of short wavr UV. But there were designs that had the phosphors coating
the inner bulb or on a separate envelope, which would not give nearly the increase in UV when the outer bulb was removed.
You can take the chlorination all the way to CCl4, the 4th C-Cl bond is about 10% lower in energy than the others and steric factors come into play,
but that just means taking additional time. |