CBS "Blue Bloods" re-writes chemistry of KCl

On "Blue Bloods" on 29 Oct 2010, the killing agent was purportedly potassium chloride (KCl) administered orally with a designer drug M-cat.

The police identified the deadly KCl by heating it over a Bunsen burner, at which point the white solid turned purple.

In the real world KCl is taken orally in drugs such as K-Dur, Klor-Con, Micro-K, Slow-K and Kaon Cl. The lethal oral dose of KCl, measured in terms of the LD50, is around 2.5g/kg (meaning that a lethal dose for 50% of people weighing 75kg (165 lb) is about 190g (6.7 ounces). The amount of KCl in the little piece of M-cat would not be fatal.

In the real world, KCl melts at 770degC, and does not turn purple. [Materials with potassium cations can give a purple color in a flame test; wikipedia: As with other compounds containing potassium, KCl in powdered form gives a lilac flame test result. This is not a unique test for KCl. The "Blue Bloods" segment did not depict a flame test. See a video of a flame test. ]

The episode also delved into Twitter.

And, yes, the chemistry teacher did it.