Thanks for A2A Valency is the number of electrons that need to be added or Charge is the value attained by the atom after removal or addition of electron/. Home Up Nuclear Charge Main Energy Levels Valence Electrons Shielding The valence electrons are the electrons in the last shell or energy level of an atom. They do The valence electrons increase in number as you go across a period. do u no that when an atom gains electrons it also gains a charge? hope so this could get long. but neways. if an atom, lets say oxygen, with 6.
When elements share electrons, a strong covalent bond is formed. When an element gives away an outer electron, it results in oppositely charged ions that are held together by a weaker ionic bond. Ionic Bonds All elements start with a balanced charge. That is, the number of positively charged protons equals the number of negatively charged electrons, resulting in an overall neutral charge. However, sometimes an element with only one electron in an electron shell will give up that electron to another element that needs only one electron to complete a shell.
What Are Valence Electrons & How Are They Related to the Bonding Behavior of Atoms? | Sciencing
When that happens, the original element drops down to a full shell and the second electron completes its upper shell; both elements are now stable. However, because the number of electrons and protons in each element are no longer equal, the element that received the electron now has a net negative charge and the element that gave up the electron has a net positive charge.
The opposing charges cause an electrostatic attraction that pulls the ions together tightly into a crystal formation.
This is called an ionic bond. An example of this is when a sodium atom gives up its only 3S electron to fill the last shell of a chlorine atom, which needs only one more electron to become stable.
Covalent Bonds Instead of giving away or receiving electrons, two or more atoms may also share electron pairs to fill their outer shells.
This forms a covalent bond, and the atoms are fused together into a molecule. An example of this is when two oxygen atoms six valence electrons encounter carbon four valence electrons.
It might seem that the two new repulsive forces would balance the two new attractive forces.Valence Electrons and Charges
If this happened, the H2 molecule would be no more stable than a pair of isolated hydrogen atoms. But there are ways in which the forces of repulsion can be minimized.
As we have seen, electrons behave as if they were tops spinning on an axis. Just as there are two ways in which a top can spin, there are two possible states for the spin of an electron: When electrons are paired so that they have opposite spins, the force of repulsion between these electrons is minimized. The force of repulsion between the protons can be minimized by placing the pair of electrons between the two nuclei.
The distance between the electron on one atom and the nucleus of the other is now smaller than the distance between the two nuclei. As a result, the force of attraction between each electron and the nucleus of the other atom is larger than the force of repulsion between the two nuclei, as long as the nuclei are not brought too close together. The net result of pairing the electrons and placing them between the two nuclei is a system that is more stable than a pair of isolated atoms if the nuclei are close enough together to share the pair of electrons, but not so close that repulsion between the nuclei becomes too large.
- How does formal charge relate to the number of valence electrons?