Cs (cesium) is in group I of the Periodic Table, and has 1 valence electron. This is very easy to lose, and so Cs loses this one electron to become the cesium cation, Cs^1+
A chlorine atom must gain one electron to complete its octet, as it has 7 electrons in its outer shell and needs 8 to achieve a stable electron configuration.
Calcium's electron configuration is [Ar] 4s2. To attain a noble gas configuration, calcium must lose 2 electrons to have the same electron configuration as argon, 4s2 3d10.
Group 7A elements (also known as Group 17) typically need to gain one electron to achieve a stable octet configuration in their outer shell. This allows them to reach a stable electron configuration similar to the noble gases.
A sulfide ion (S2-) must gain two electrons to achieve a noble gas electron configuration, similar to that of a stable, inert gas such as argon. This transfer allows the sulfide ion to fill its valence shell with eight electrons, satisfying the octet rule.
An atom becomes an ion by gaining or losing electrons. If it gains electrons, it becomes a negatively charged ion called an anion. If it loses electrons, it becomes a positively charged ion called a cation.
Selenium should gain two electrons and lose six electrons to achieve a noble gas electron configuration.
Iodine, located in Group 17 of the periodic table, has 7 valence electrons. To achieve a noble gas electron configuration (like Xenon), it must gain 1 electron to fill its valence shell and attain stability.
1 electron
sodium must lose 1 electron, helium is a noble gas it is in group 8 check your periodic table, sufide ion must gain 2 electrons
This atom must gain 3 electrons to achieve an octet.
A chlorine atom must gain one electron to complete its octet, as it has 7 electrons in its outer shell and needs 8 to achieve a stable electron configuration.
Chlorine gain an electron in chemical reactions.
Bromine's atomic number is 35, so it has 7 valence electrons. To achieve 8 valence electrons and a full outer shell, bromine needs to gain one electron.
Calcium's electron configuration is [Ar] 4s2. To attain a noble gas configuration, calcium must lose 2 electrons to have the same electron configuration as argon, 4s2 3d10.
Potassium has one electron in its outer shell. It will lose this electron to achieve the noble gas electron configuration of argon in its previous full shell.
Group 7A elements (also known as Group 17) typically need to gain one electron to achieve a stable octet configuration in their outer shell. This allows them to reach a stable electron configuration similar to the noble gases.
Halogens are in the seventh group on the periodic table, and thus have seven electrons in their outer shell. In order to attain a noble gas configuration, it must gain an electron to form an octet, which is when eight electrons are in the outer shell.