Is au an atomic element, molecular element, molecular compound or an ionic compound?

Convection is da answer my dood

The internal energy of the system we can term it as total potential energy and kinetic energy. energy flows out of the surrounding from the system then we can say that the internal energy of the final state is lower than its initials. the sign of  δesystem is negative.δesystem = efinal - einitial=-ve  efinal  ∠einitial.

13 protons and 13 electrons