Chapter 29, Problem 2Q

To determine

ToDescribe:

The formation of the molecule of ${\text{CaCl}}_{\text{2}}$.

Answer to Problem 2Q

Solution:

The molecule ${\text{CaCl}}_{\text{2}}$ can be formed by the reaction of limestone with hydrochloric acid.

Explanation of Solution

Calcium chloride occurs in nature in its hydrated form. The chemical formula of calcium chloride is ${\text{CaCl}}_{\text{2}}$. ${\text{CaCl}}_{\text{2}}$ is an ionic compound and it is composed of calcium cation, that is, ${\text{Ca}}^{\text{2+}}$ and two chlorine anions, that is, ${\text{Cl}}^{\text{-}}$.

The calcium cation has a valency of two. Therefore, the calcium metal is bivalent. This bivalent calcium atoms forms an ionic bond with the two chlorine atoms.

The bond formation is shown below:

Given:

Chemical formula of Calcium Chloride, that is, ${\text{CaCl}}_{\text{2}}$.

Formula used:

${\text{CaCO}}_{\text{3}}\text{+2HCl}\to {\text{CaCl}}_{\text{2}}{\text{+CO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O}$

Calculation:

Calcium chloride is formed by the chemical reaction between limestone, that is, ${\text{CaCO}}_{\text{3}}$ and hydrochloric acid, that is, $\text{HCl}$.

The chemical reaction is as follows:

${\text{CaCO}}_{\text{3}}\text{+2HCl}\to {\text{CaCl}}_{\text{2}}{\text{+CO}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O}$

Here, ${\text{CO}}_{\text{2}}$ is Carbon dioxide and ${\text{H}}_{\text{2}}\text{O}$ is water.

This is the equation showing the formation of ${\text{CaCl}}_{\text{2}}$.