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Name: Don P.
Status: educator
Age: 40s
Location: N/A
Country: N/A
Date: Saturday, October 12, 2002

I have seen lots of baking soda plus vinegar questions and answers, but I was wondering what the formula was for a ant-acid (Tums) plus vinegar reaction was. Can you help?


Tums is mainly calcium carbonate (CaCO3). Vinegar is mainly acetic acid (HC2H3O2). The reaction goes like this:

CaCO3 + 2 HC2H3O2 ==> Ca(C2H3O2)2 + H2CO3

The H2CO3 (carbonic acid) is unstable. It disproportionates (decomposes) into CO2 (gas bubbles) and H2O

ProfHoff 489

The active ingredient in Tums is calcium carbonate, CaCO3, and in vinegar is acetic acid, CH3CO2H.

The reaction is:
CaCO3 + 2 CH3CO2H ----> CO2 gas + H2O + Ca(+2) + 2 CH3CO2(-1)

Vince Calder

Not much different. Baking soda is sodium bicarbonate, the active ingredient in Tums is calcium carbonate.

CaCO3 + 2 CH3COOH --> Ca(CH3COO)2 + H2O + CO2

Richard E. Barrans Jr., Ph.D.
Director of Academic Programs
PG Research Foundation, Darien, Illinois

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