In any atom with more than two electrons, inner electrons have a repelling effect on outer electrons, reducing the net attraction of the nucleus for the outer electrons. This effect is known as shielding, and it is respo... More »

An electron is a negatively charged subatomic particle that orbits around the nucleus of an atom. The negative charge of the electrons is balanced by the positive charge of the protons in the nucleus. Electrons have a mu... More » Science Biology Cells

The nucleus of an atom is surrounded by an electron cloud that is held in place by an electromagnetic force. The nucleus accounts for significantly more of the atom's total mass than the cloud, although the cloud account... More »

A nitrogen atom's appearance consists of a nucleus that's surrounded by one orbital containing two electrons and a second orbital containing five electrons. The total number of electrons in one atom of nitrogen can be de... More »

The Bohr model of carbon has a central nucleus containing six protons and six neutrons, encircled by an inner orbit of two electrons and an outer orbit of four electrons. The two orbits represent different energy levels ... More »

The Bohr model for nitrogen has a central nucleus with seven neutrons and seven protons, a first energy ring with two electrons and a second energy ring with five electrons. A more detailed version shows two electrons in... More »

The core, or dense center of an atom, is called the atom's nucleus. The nucleus contains protons, which have positive charges, and neutrons, which have no charge and are neutral. More »