(a) Carbon dioxide

In the laboratory, CO₂ can be prepared by the action of dilute hydrochloric acid on calcium carbonate. The reaction involved is as follows:-

CaCO₃ + 2HCl_(aq)→ CaCl_2(aq) + CO_2(g) + H₂o

CO₂ is commercially prepared by heating limestone. The reaction involved is:-

CaCO₃→ CaO + CO₂↑

(b) Carbon monoxide

In the laboratory, CO is prepared by the dehydration of formic acid with conc. H₂SO₄ at 373k. the reaction involved is:-

HCOOH H₂O + CO↑

CO is commercially prepared by [assing steam over hot coke. The temperature should be 473-1273K. the reaction is:-

C_(s) + H₂O → CO_(g) + H_2(g)