Answer:
The Aufbau Principle
Explanation:
In the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy level before occupying higher-energy levels.
Displacement, usually the method that is used to measure the volume of an irregularly shaped object.
That's a ionic compound because it has a metal and polyatomic parts within the chemical formula.
Answer: The structure of an atom, theoretically consisting of a positively charged nucleus surrounded and neutralized by negatively charged electrons revolving in orbits at varying distances from the nucleus, the constitution of the nucleus and the arrangement of the electrons differing with various chemical elements.
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