What is a yellow or greenish yellow gas, first prepared by Davy, evolved from potassium chlorate and hydrochloric acid. It is supposed to consist of chlorine tetroxide with some free chlorine called?

euchlorine — A yellow or greenish yellow gas, first prepared by Davy, evolved from potassium chlorate and hydrochloric acid. It is supposed to consist of chlorine tetroxide with some free chlorine. (Webster's 1913.)

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