Chapter 11, Problem 11STP

Interpretation Introduction

Interpretation: The balanced chemical reaction for the reaction between limewater and carbon dioxide should be determined.

Concept Introduction: A chemical reaction is said to be balanced when the number of atoms for each element in the equation is the same on both sides, that is reactants and products.

Answer to Problem 11STP

  ${\text{Ca(OH)}}_2{\text{(s) + CO}}_{\text{2}}\text{(g) }\to {\text{ CaCO}}_3{\text{(s) + H}}_2\text{O(l)}$

Explanation of Solution

A skeleton equation is defined as a chemical equation that uses the formulas of the reactants and products involved in a chemical reaction. It does not indicate the amounts of the reactants and products. For this equation, an arrow is used to differentiate reactants and products, the reactants are written on the left side of the arrow whereas products are written on the right side of the arrow.

The formula of the reactants and the physical states of each substance involved in the reaction between limewater and carbon dioxide to form calcium carbonate and water is:

limewater, ${\text{Ca(OH)}}_2\text{(s)}$

(s) indicates the solid state.

Carbon dioxide, ${\text{CO}}_{\text{2}}\text{(g)}$

(g) indicates the gaseous state.

The formula of the products and the physical states of each substance involved in the reaction between limewater and carbon dioxide to form calcium carbonate and water is:

Calcium carbonate, ${\text{CaCO}}_3\text{(s)}$

Water, ${\text{H}}_2\text{O(l)}$

(l) represents the liquid state.

The reactants are separated from the products with an arrow and two reactants and products are separated using the plus sign. Thus, the skeleton equation for a chemical reaction, limewater and carbon dioxide:

  ${\text{Ca(OH)}}_2{\text{(s) + CO}}_{\text{2}}\text{(g) }\to {\text{ CaCO}}_3{\text{(s) + H}}_2\text{O(l)}$

The number of atoms on the reactant side is:

  $\begin{array}{l}\text{Ca = 1}\\ \text{C = 1}\\ \text{O = 4}\\ \text{H = 2}\end{array}$

The number of atoms on the product side is:

  $\begin{array}{l}\text{Ca = 1}\\ \text{C = 1}\\ \text{O = 4}\\ \text{H = 2}\end{array}$

From the above number of atoms in the reactant and product side, it can be concluded that all the number of atoms for every element are the same thus, it is a balanced chemical reaction.

Hence, the balanced chemical reaction for the reaction between limewater and carbon dioxide is, ${\text{Ca(OH)}}_2{\text{(s) + CO}}_{\text{2}}\text{(g) }\to {\text{ CaCO}}_3{\text{(s) + H}}_2\text{O(l)}$ .