Question

the movie below shows some molecules in a tiny sample of a mixture of gases. drag the slider to see how the molecules move. does a chemical reaction happen during this movie? yes no if a chemical reaction does happen, write a balanced chemical equation for it.

Explanation:

Step1: Observe the molecules

There are chlorine - chlorine ($Cl_2$) molecules and hydrogen - chlorine ($HCl$) molecules. Initially, there are $2$ $Cl_2$ molecules and some $HCl$ molecules. After the movement, new molecules are formed.

Step2: Identify the reaction

The reaction is between chlorine and hydrogen to form hydrogen - chloride. The chemical equation is $H_2 + Cl_2
ightarrow2HCl$. But we need to balance it based on the atoms present in the sample. Since we see only chlorine and hydrogen - chlorine in the sample, and assuming hydrogen is present in the mixture in a reactive form, the reaction is $Cl_2 + H_2
ightarrow2HCl$.

Answer:

$Cl_2 + H_2
ightarrow2HCl$