Question

Which of the following statements regarding carbon dioxide are true?

• A. Formed by incomplete combustion of hydrocarbons
• B. Forms acidic aqueous solution
• C. Obtained by the reaction between carbonates and acids
• D. Used as a reducing agent in the metallurgy

Answer 1

Answer: (B), (C)

The correct options are
B

Forms acidic aqueous solution

C

Obtained by the reaction between carbonates and acids

• Carbon dioxide on reaction with water produces carbonic acid as shown below.

${\mathrm{CO}}_2\left(g\right)+H_{2}O\left(l\right)\to H_2{\mathrm{CO}}_3\left(\mathrm{aq}\right)\mathrm{Carbon}\mathrm{Water}\mathrm{Carbonic}\mathrm{dioxide}\mathrm{acid}$

• Acids react with carbonates and bicarbonates to liberate carbon dioxide and water along with metal salt. For example,

${\mathrm{MgCO}}_3\left(s\right)+2\mathrm{HCl}\left(\mathrm{aq}\right)\to {\mathrm{MgCl}}_2\left(s\right)+H_{2}O\left(l\right)+{\mathrm{CO}}_2\left(g\right)\mathrm{Magnesium}\mathrm{Hydrochloric}\mathrm{Magnesium}\mathrm{Water}\mathrm{Carbon}\mathrm{carbonate}\mathrm{acid}\mathrm{chloride}\mathrm{dioxide}$

• Carbon monoxide (CO) is formed by incomplete combustion of hydrocarbons.

• Coke, which is an amorphous form of carbon is used as a reducing agent in metallurgy.