Question

Is $C{O}_2$ an acid or base?

Answer 1

Hint: Acids are generally those substances which are capable of donating a proton i.e. hydrogen atom to another substance while bases are those substances which are able to accept a hydrogen ion from an acid.

Complete answer:
Acids are generally those substances which are capable of donating a proton i.e. hydrogen atom to another substance while bases are those substances which are able to accept a hydrogen ion from an acid.
$C{O}_2$ is not termed as an acid by itself since it does not contain hydrogen ions represented by $$$$$H^{+}$. $C{O}_2$ becomes carbonic acid when it dissolves in water. Carbonic acid represented by the formula $H_{2}C{O}_3$ is known as weak acid as it dissociates $H^{+}$ ions. Therefore, carbonic acid is termed as a weak acid which acidifies the solution formed when some of the carbon dioxide dissolves in the water.
When carbon dioxide gas is dissolved in water it causes the water to be acidic. On the other hand bases like baking soda decrease the acidity of water from dissolved carbon dioxide gas.
Hence from the above discussion we can say that $C{O}_2$ is an acid.

Note:
Acids are generally sour in taste like lemon in which citric acid is present and it turns blue litmus paper to red. Bases are bitter in taste and turn red litmus paper into red. A base that can be dissolved in water is known by the term alkali and when these substances chemically react with acids they form salts.