Q80P - Chemistry: Molecular Nature Of Matter And Change

Question

Consider a mixture of 10 billion ${\mathbf{O}}_{\mathbf{2}}$ molecules and 10 billion ${\mathbf{H}}_{\mathbf{2}}$ molecules. In what way is this mixture similar to a sample containing 10 billion hydrogen peroxide $\left(H_2{O}_2\right)$ molecules? In what way is it different?

Step-by-Step Solution

Answer

Both the mixtures have the same number of ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ molecules. But the total number of atoms is different in both the mixtures.

Step 1: Identify similarities between mixture I and mixture II

Mixture I contain 10 billion ${\mathbf{O}}_{\mathbf{2}}$ molecules and 10 billion ${\mathbf{H}}_{\mathbf{2}}$ molecules, so in total 20 billion molecules are present and in mixture II, 10 billion molecules ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ are present. A ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ molecule is formed from the combination of oxygen and hydrogen atoms. So, 10 billion ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ molecules contain 10 billion ${\mathbf{H}}_{\mathbf{2}}$ and 10 billion ${\mathbf{O}}_{\mathbf{2}}$ molecules. Therefore, we can say that both the mixtures have the same number of ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ molecules.

Step 2: Determine the difference between mixture I and mixture II

Mixture I contain 10 billion ${\mathbf{O}}_{\mathbf{2}}$ molecules and 10 billion ${\mathbf{H}}_{\mathbf{2}}$ molecules, so a total of 20 billion molecules are present, whereas mixture II contains only 10 billion molecules ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ In mixture I, ${\mathbf{H}}_{\mathbf{2}}$ and ${\mathbf{O}}_{\mathbf{2}}$ present in form of molecules, these are not connected with each other, but in mixture II, it ${\mathbf{H}}_{\mathbf{2}}{\mathbf{O}}_{\mathbf{2}}$ is formed by bonding between the atoms of the different elements.