The Halide gasses (Fluorine, Chlorine, Bromine etc. ) because they only need to gain 1 electron to fill its outermost energy level.
The oxidation number of an element tells you the charge that the element would have if electrons were transferred completely during the formation of a compound. It can help to determine the type of chemical reactions that an element is likely to undergo.
Magnesium
Any atom of any element has no net electrical charge. The number of "outer" electrons is irrelevant, because the charge of all the electrons is balanced by an equal number of protons in the nucleus of the atom. However, the number of outer electrons is highly relevant to the charge of the most likely ion formed from an atom of an element by chemical reaction: Magnesium and other atoms with two outer electrons almost always form cations with 2 net positive charges when the atoms react chemically with some atom of another element, because these two outer electrons are less tightly bound to the atomic nucleus than any other electrons of the atom.
An element with 120 protons and 2 electrons would belong to Group 2 on the periodic table, also known as the alkaline earth metals group. Elements in this group typically have 2 valence electrons and exhibit similar chemical properties due to their electronic configuration. Examples of elements in Group 2 include beryllium, magnesium, calcium, strontium, and barium.
An element with an atomic number of 14, such as silicon, would have 4 valence electrons. Valence electrons are the electrons in the outermost energy level of an atom, which corresponds to the group number of the element on the periodic table.
The oxidation number of an element tells you the charge that the element would have if electrons were transferred completely during the formation of a compound. It can help to determine the type of chemical reactions that an element is likely to undergo.
Li, or lithium, is the element most likely to lose electrons in a chemical bond. Lithium has 1 valence electron.
The charge an element would have if it lost or gained electrons
Metals are the elements that usually lose electrons in their chemical reactions. This is because they have few electrons in their outermost shells which are easily lost.
Chemical Reactions would not exist, since unstable electrons are needed to start a Chemical Reaction, All the molecules would be stable, so they would not need to undergo change to become more stable.
Chlorine would be expected to be more reactive than phosphorus because it is higher in the periodic table and has a higher electronegativity, making it more likely to gain electrons in a chemical reaction.
Yes and no; the number of protons determine the valance number of electrons. The valence level of electrons and how full/empty it is largely determines an elements chemical behavior. I would say that valence electrons are the main determinant, but that is predetermined by protons.
They determine many things. They can be used to predice hybridization, determine octet, be used to assign formal charges. The simplest answer would be for a intro to chem class, they determine the number of electrons in the atom's "outer ring"
They are the electrons in the outermost shell, and are the ones involved in most chemical reactions.
There is no element with a "charge of 18". Charges are determined by electrons, so for an atom to have a charge of ±18, it would have to lose or gain 18 electrons - something an atom wouldn't do. Perhaps you mean atomic number of 18, which would be argon or Ar.
You think probable to the chemical symbol of an element.
An element with a higher electronegativity value would be more likely to pull in electrons during the formation of a compound. Elements like fluorine, oxygen, and nitrogen, which are towards the upper right of the periodic table, tend to have high electronegativity values.