Calcium carbonate reacts with hydrochloric acid (hcl) to produce calcium chloride, water and carbon dioxide. you need to have 267 grams of carbon dioxide for another process, so you need to start with __ mol hydrochloric acid.
__ caco3 + __ hcl → __ cacl2 + __ h2o + __ co2

Hbr dissociates to form h+ and br-ca(oh)2 dissociates to form ca2+ and 2oh-the h+ and oh- react to form waterassuming the reactants are dissolved in water, the net reaction is h+ + oh- —> h2oif you’re asked to show all components of the reaction, the complete reaction is 2hbr + ca(oh)2 —> cabr2 + 2h2o

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