What is the definition of thermal equilibrium

Two physical systems are in thermal equilibrium if there is no net flow of heat between them.

Explanation:

Two Physical systems are said to be in thermal equilibrium if there is no net flow of heat energy between them when they are connected and both of the system is at the same temperature.

Thermal equilibrium is of two varieties i.e Two thermally connected bodies and Internal thermal equilibrium.

If two bodies are thermally connected to each other then there will only transfer of the heat to maintain equilibrium but no transfer of the matter and mass.

Also, a internal thermal equilibrium is maintained in a isolated body where there is no transfer of the heat from the body outside or inside of it.

Thermal equilibrium follows zeroth law of thermodynamics which says that Two bodies are in thermal equilibrium with each other if they individually are in thermal equilibrium with a third body.

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of c is as shown here in the image.

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.