How is it possible for a metal to transfer thermal energy?

First we must understand the question and what it is asking from us. Thermal energy is just heat and the question is asking how can heat spread from one side of the metal to the other. Well if we look at the atomic point of view of the metal which we say is Iron as an example is made from metal ions. These are positive cations which means it has a positive charge and they are surounded by electrons which have a negative charge. However in metals the electrons are called delocalised electrons. This means that these electrons are free to move and carry heat with them as well as charge which is known as electricity. This means that if you touch one side of the cold iron bar, your hear from your hands is transferred into these electrons and as they move and bump into other electrons they transfer this heat along with them.