This is Ken deGraff on the rxn of Alka Seltzer H2O
NaHCO3​(s) H2​O(l)→NaOH(aq) CO2​(g) H2​O(l)
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If I wanted specifics, I’d do the stoichiometry, but I’m not, so I won’t. CO2 is a resultant of the acid-base reaction. There’s no co2 in the tablets"
The g means gas Ken