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Electrons occupied certain discrete energy levels around the nucleus.
Inner shell electrons are electrons that are located closer to the nucleus of an atom, shielded by outer electron shells. They have lower energy levels compared to outer shell electrons and are generally not involved in chemical reactions.
The reactivity of an atom is due to its number and arrangement of __________ in the outer energy level (or orbit). your question was confusing but I was able to interperet it. the answer is Electrons
There are three electrons in boron's outer energy level.
Electrons in the outer orbit of an atom can become free when they absorb enough energy, usually in the form of heat or light, to overcome the attractive force of the nucleus. This allows the electrons to move into higher energy levels or even leave the atom entirely, resulting in ionization.
The sharing of electrons in the outer energy levels of two atoms is called bonding.
Nitrogen has atomic number = 7. The outer shell has 5 electrons, it requires 3 more electrons to complete the outer energy shell.
Sharing of electrons in the outer energy level of two atoms results in a covalent bond.
Beryllium and magnesium have two electrons in their outermost energy level, as do all Group 2 elements.
The outer shell is called the valence shell
Nonmetals almost have a full outer energy level while metals have few electrons in their outer energy level.
Valence electrons
1-2
chemical bond
An element with 2 energy levels and 2 electrons in the outer layer is beryllium (Be). Beryllium has an atomic number of 4, with 2 electrons in the first energy level and 2 electrons in the second energy level, making it a neutral atom.
The element with 3 energy levels and 8 neutrons in its outer energy level is oxygen, with the symbol O. Oxygen has 8 protons and 8 neutrons in its nucleus, with 2 electrons in its inner energy level and 6 electrons in its outer energy level.
Helium and neon will have their outer energy level filled with two electrons. Helium has 2 electrons in its only energy level, while neon has 8 electrons in its second energy level.