Valence shell
The outer-most shell of an atom is called the valence shell. It is involved in forming chemical bonds with other atoms.
Protons and neutrons form the nucleus of an atom while electrons form the shell of an atom. The electrons in the shell of the atom exist in distinct layers. Those in the outer layer take part in chemical reactions and are involved in electricity. Electrons are also basic particles called leptons. Protons and Neutrons are not basic particles but are composite particles called haldrons. They consist of three basic particles called quarks. Quarks are a basic particle called fermions.
Valence
You just said it, electrons. The "shell" is just an energy level. It is called a shell because it surrounds the atom, but it is just the electrons. Since there is no way to determine the exact location of an electron, it is referred to as an "electron cloud."
The negatively charged particles of an atom are in an outer shell.
Valence shell
The outer-most shell of an atom is called the valence shell. It is involved in forming chemical bonds with other atoms.
It is a shell, as in a cockle shell or oyster shell.
An egg with an outer hard shell is called the cuticle or bloom. It helps keep out bacteria and dust.
the shell
the shell
The outer shell of a watermelon is called the rind or peel. It is the tough outer layer that is typically green in color and protects the fruit inside.
The outer layer of a sea shell is called the exoskeleton or the shell's outer casing. It is composed of calcium carbonate and provides protection for the soft tissues of the animal inside.
Valence shell and Ultimate Shell
The outer shell of a plane can be called the skin. The smoother the skin the faster the plane passes through the air.
The outer covering of an egg is called the shell.