The story
From penta- + thionic + acid, since it contains five atoms of sulphur.
Etymology from Wiktionary, CC BY-SA 4.0.
pentathionic acid
Today it means: The dibasic acid HSO₃-S₃-SO₃H Full definition →
Today it means: The dibasic acid HSO₃-S₃-SO₃H Full definition →
From penta- + thionic + acid, since it contains five atoms of sulphur.
Etymology from Wiktionary, CC BY-SA 4.0.