How does an atom react at low temperatures?

Answer 1

Chemical reactions require what is known as an "activation energy" to get started; if the reaction is exothermic, it may produce enough energy that it becomes self-sustaining. At lower temperatures there is less energy available, and so atoms are less likely to engage in chemical reactions.

Answer 2

At low temperatures, atoms have less thermal energy and move slower. This can lead to atoms forming tighter bonds and transitioning to a more ordered state, such as transitioning from a gas to a liquid or solid phase. In some cases, atoms at low temperatures may exhibit quantum behavior, like superfluidity or superconductivity.