Question

Which of the following describes the reaction between carbon dioxide and limewater?

• A. ${\text{CO}}_2\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to {\text{CaCO}}_3\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$​
• B. $\text{CO}\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to {\text{CaCO}}_3\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$
• C. ${\text{CO}}_2\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to \text{CaO}\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$
• D. $\text{CO}\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to \text{CaO}\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$

Answer 1

The correct option is A

${\text{CO}}_2\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to {\text{CaCO}}_3\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$​

When carbon dioxide is passed through limewater, calcium carbonate is formed. This makes the limewater turn milky. The reaction is as follows:
${\text{CO}}_2\text{(g)}+{\text{Ca(OH)}}_2\text{(aq)}\to {\text{CaCO}}_3\text{(s)}+{\text{H}}_2\text{O}\text{(l)}$​