What process describes the transfer of heat through matter by molecular activity?

Silver tarnishes as silver metal reacts with hydrogen sulfide, h2s, in the air. in this reaction, dark silver sulfide, au2s, covers the surface of silver. when silver is polished, this coating of silver sulfide can be removed from the surface. this makes the silver shiny again. enter the coefficients that balance the tarnishing reaction equation. (type 1 for no coefficient.)

The excretory system,need answers for all: )

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.