The atom.
An atom is the smallest particle of an element that still has the chemical characteristics of that element
If it is an element, then the smallest particle that retains the characteristics of the element is an atom. If it is a diatomic element, then the smallest particle that retains the characteristics of the element is a molecule. If it is a molecular compound, then the smallest particle that retains the characteristics of the compound is a molecule. If it is an ionic compound, the smallest particle that retains characteristics of the compound is a formula unit.
atoms
This particle is the atom.
An atom
The smallest particle of any substance that maintains elemental characteristics and identity is an atom. Conversely a pure elemental sample if divided indefinitely into smaller pieces would ultimately yield the atom.
The smallest particle of an element is called an atom.
An atom is the smallest building block of matter that retains the characteristics of that matter.
An atom is the smallest building block of matter that retains the characteristics of that matter.
An atom is the smallest building block of matter that retains the characteristics of that matter.
A molecule is the smallest part of a compound that still retains the properties of said compound. As the atom is the smallest particle of an element into which it can be divided and still retain all the properties of that element, the molecule is the atom's analog for a compound.
No. This is a definition of an atom. Electrons are only part of atoms.