An element that has two outer electrons is carbon. Carbon would not use the energy to gain six more electrons when it can easily get rid of the two outer electrons.
Beryllium would tend to lose its two electrons when forming a bond because it is easier to lose its two valence electrons rather than gain an additional five in order to obtain a full outer shell.
Electrons
Without knowing the specific circumstances of your question, it's not possible to be precise, but in general the electronegativity of an element is a big factor in determining its reactions.
The periods near the top, i presume because they have less shielding from other electrons in their orbitals, therefore there will be a larger nuclear pull so easier to attract electrons. Obviously a element with a full shell or 1 or 2 electrons in it isn't really going to gain electrons and Transition metals are weird. Hope this helps :)
Atom in its elemental form is in neutral state. Two or more similar kind of atoms combine to form an element. Every element has a particular characteristic that is different from other element.
Nonmetals seek to gain electrons to achieve a full outer electron shell and attain stability through a full octet. This process allows nonmetals to achieve a more stable electron configuration by filling their outer electron shell and forming negative ions.
It means that the element will add, gain or share electrons so that the outer most shell has 8 electrons.
It is a Group 2 element, therefore it has two outer-shell electrons. To gain a full outer-shell, it loses two electrons to form a cation (cations are positive ions)
The oxidation state of an element is determined by the number of electrons it loses or gains when forming a compound. It depends on the element's position in the periodic table and its ability to either lose or gain electrons to achieve a stable electron configuration. The rules for assigning oxidation states are based on the idea that atoms tend to gain or lose electrons to achieve a full outer shell.
Arsenic, with an atomic number of 33, will gain 3 electrons to have a filled outer shell, achieving stability with 8 electrons in its outer shell like a noble gas.
The elements can only be stable when it complete is octate in its outer most orbit has 8 electrons in its outer most orbit by gaining or losing energy
Tellurium tends to gain electrons in chemical reactions to achieve a full outer shell and attain the stable electron configuration of a noble gas. It typically forms -2 oxidation state by gaining two electrons.
An element can either gain or lose electrons to achieve a noble gas electron configuration. Such an electron configuration gives an atom of an element a full outer shell, thereby making that element's ion nonreactive. Metals tend to lose electrons, and become cations, whereas nonmetals tend to gain electrons, and become anions. The amount of electrons an element gains of loses is based on the group/family the element is found in on the Periodic Table.
An element's most likely oxidation state is often related to its valence electrons because elements tend to gain or lose electrons to achieve a stable electron configuration. The number of valence electrons an element has can determine how many electrons it will gain or lose to reach a full or empty outer shell, resulting in a specific oxidation state.
If 2 are attracted to each other then they exchange (lose or gain) electrons so that their outer shell can be full. You should google bohrs theory and diagrams.
Generally metals lose electrons and nonmetals gain electrons.
Its valency is 3 i.e. 8-5.The element is a non metal since it has 5 electrons in the outermost shell.Hence, it is very difficult for the element to loose 5 electrons and would be easier togain 3 electrons .Hence, the element gains 3 electrons and thus we consider its valencyto be 8- no. of valence electrons.