The Belousov–Zhabotinsky reaction is a chemical oscillator that belongs to this class of reactions, whose “substrate-depletive” type typically consists of a slow and a fast reaction. For 10 points each:
[10m] Name this class of reactions. Hans Heinrich Landolt discovered one of these reactions in which a colorless mixture suddenly turns dark blue after a short time delay.
ANSWER: clock reactions [or chemical clocks; accept, but DO NOT REVEAL, iodine clock reaction]
[10e] The Landolt clock reaction is more commonly named for this element, which, when complexed with starch, gives the mixture its dark blue color. This purple halogen is found directly below bromine in the periodic table.
ANSWER: iodine [or I; accept iodine clock reaction; accept iodine-starch test]
[10h] The Belousov–Zhabotinsky reaction exemplifies this phenomenon, also seen with the hydrolysis of gamma valerolactone. Nonlinear rate equations and sigmoidal product formation curves can be seen in this phenomenon.
ANSWER: autocatalysis [or autocatalytic reactions]
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