Lithium loses electrons.
An atom with an atomic number of 20 has 20 electrons. The number of electrons in an atom is equal to its atomic number.
In a neutral atom the number of electrons equals the number of protons (atomic number), so the atom in question would have 30 electrons.
An atom with atomic number 8 corresponds to oxygen. Oxygen has 8 electrons because the number of electrons in an atom is equal to its atomic number.
The number of protons is equal to atomic number; in a neutral atom the number of electrons is also equal to the numbers of protons.
In a neutral atom, the number of electrons is always the same as the atomic number.
The number of electrons in an atom can be determined by looking at the atomic number of the element on the periodic table. The atomic number represents the number of protons in the nucleus of an atom, which is equal to the number of electrons in a neutral atom.
In a neutral atom the number of protons is equal to the number of electrons. And by definition the atomic number of an atom is equal to the number of protons in it. So the atomic number of a neutral atom is equal to the number of protons or the number of electrons in the atom.
The atomic number is equal to the number of protons in an atom, which also corresponds to the number of electrons in a neutral atom. This means that the atomic number gives you the total number of electrons in a neutral atom of that element.
The atomic number is the number of protons and therefore, assuming the atom is neutral, the number of electrons. You would need to additionally know the atomic mass to figure out the number of neutrons.
The atomic number represents the number of protons in an atom's nucleus, which is also equal to the number of electrons in a neutral atom. Core electrons are those that are closest to the nucleus and are not involved in chemical bonding. The number of core electrons in an atom is equal to the difference between the atomic number and the number of valence electrons.
Atomic number of an atom shows the number of protons in the nucleus of the atom. OR Atomic number of an atom is the number of electrons in the atom when the atom neutrally charged
Atomic number = number of protons as well as the number of electrons in an atom.