Question

Formation of hydrogen chloride from hydrogen and chlorine is an example of ____________ (electrochemical/photochemical) reaction.

Answer 1

• A photochemical reaction is a chemical reaction started by the absorption of energy in the form of light, resulting in specific products.
• Photochemical reactions are driven by the number of photons that can activate molecules to cause the desired reaction.
• During a photochemical reaction, these molecules tend to form a new structure.

For example:

• $\underset{\mathrm{Hydrogen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}\stackrel{\mathrm{light}}{\to }\underset{\mathrm{Hydrogen}\mathrm{chloride}}{2\mathrm{HCl}\left(\mathrm{g}\right)}$

Therefore, the formation of hydrogen chloride from hydrogen and chlorine is an example of a photochemical reaction.