Methane does not react with chlorine in dark. Why?

A hydro carbon C_5H_(10) does not react with chlorine in dark but gives a single monochloro compound C_5H_9Cl in bright sun light. Identify the hydrocarbon.

What happens when Methane reacts with chlorine in diffused sunlight.

Which of the following does not react with oxygen directly? Zn, Ti, Pt, Fe.

Dry chlorine cannot bleach. Why?

Negative electron gain ethalpy of fluorine atom is less than that of chlorine atom. Why?

How does zinc react with dilute Hydrochloric acid?