A compound contain 53% Al and 47% O by mass . what is the empirical formula of this compound ?

In a copper wire, a temperature increase is the result of which of the following

Is a pencil falling to the floor anon contact force, a force, or a contact force

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.