for all elements, excluding hydrogen, there are 2 electrons in the first energy level. Hydrogen is the exception of this because it only has a single electron, thus it only has 1 in its first and only energy level.
The period tells you how many energy levels an atom has.
There are 2 elements in the first period of the periodic table: Hydrogen and Helium.
Period 1 of the periodic table has only one electron shell. This shell can hold a maximum of two electrons, which are found in the hydrogen and helium atoms. Therefore, elements in this period have their electrons in the first and only shell, representing the simplest atomic structure.
period 3 elements in the periodic table have 3 electrons in there outher shell hence the name.
The fourth electron shell is filled by krypton. Krypton is the last element in the fourth period on the periodic table. Each of the periods represents an electron shell. Elements in the first period have electrons in the first shell; elements in the second period have electrons in the second shell; and so on.
The period tells you how many energy levels an atom has.
There are 2 elements in the first period of the periodic table: Hydrogen and Helium.
Period 1 of the periodic table has only one electron shell. This shell can hold a maximum of two electrons, which are found in the hydrogen and helium atoms. Therefore, elements in this period have their electrons in the first and only shell, representing the simplest atomic structure.
period 3 elements in the periodic table have 3 electrons in there outher shell hence the name.
Eight, except for helium, which needs only two because: it has only s electrons' each period or atomic shell number can include only two s electrons; and the first period can have no p, d, or f electrons.
2 electrons.
Cl is in the 17 group. It is in the 3rd period. It has 3 energy levels.
there are two electrons the first shell hold
Two electrons can fit in the first shell
Two electrons can be housed in the first energy level.
The fourth electron shell is filled by krypton. Krypton is the last element in the fourth period on the periodic table. Each of the periods represents an electron shell. Elements in the first period have electrons in the first shell; elements in the second period have electrons in the second shell; and so on.
The shell model explains the organization of the periodic table. The elements in the first period have electrons in the first shell; the elements in the second period have electrons in the first two shells; the elements in the third period have electrons in the first three shells; and so on.