What is the primary mechanism by which energy is transferred from one atom to another in conduction?

The primary mechanism of energy transfer from one atom to another in conduction is indeed through direct contact. In conductive materials, such as metals, atoms are arranged closely together. When energy, typically in the form of heat, is applied to one part of the material, the atoms begin to vibrate more vigorously. This increased kinetic energy is then transferred directly to adjacent atoms through collisions as they come in contact with one another.

As one atom vibrates more due to the incoming energy, it imparts some of that energy to neighboring atoms during these interactions, propagating the energy through the material. This process continues until thermal equilibrium is reached, demonstrating how conduction relies on the physical interaction between atoms in a solid.

The other options involve different methods of energy transfer. Electromagnetic waves pertain to radiation, which is not related to conduction. Convection currents involve the movement of fluids to transfer energy through bulk movement rather than direct atomic contact. Finally, chemical reactions involve energy changes due to bond formation or breaking, not simply transferring energy between existing atoms through contact. Thus, direct contact is the defining characteristic of conduction.