What is the difference between an atom and a mixture?

According to coulomb's law, how would the electrical force between particles change if the product of their electrical charge increased?

An electron moved from shell n = 2 to shell n = 1. what most likely happened during the transition? a fraction of a photon was added. a photon of energy was absorbed. a fraction of a photon was removed. a photon of energy was released.

Analyze how limestone is weathered and identify the features that are formed as a result of this dissolution