Question

practical uses of CO²

Answer 1

Carbon dioxide (CO2) is a slightly toxic, odorless, colorless gas with a slightly pungent, acid taste.  Carbon dioxide is a small but important constituent of air.  It is a necessary raw material for most plant life, which remove carbon dioxide from air using the process of photosynthesis. 

Answer 2

CO2 is used in the manufacturing of casting molds to enhance the hardness.
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