Argon.
The group number 17 comprises of elements that has seven electrons in their own outer level.
The valence electrons are the outer most electrons and the principal energy level in which they belong will vary for element to element and generally corresponds to the period number in which the element is present
The element's period indicates the number of energy levels or electron shells that its electrons occupy. Each period corresponds to a new energy level being filled by electrons. Moving from left to right across a period, the number of energy levels increases by one as you go from one element to the next.
The period number of an element corresponds to the energy level of its outermost electrons. Elements in the same period have the same number of electron shells. As you move from left to right across a period, the number of protons and electrons increases, resulting in higher effective nuclear charge, which affects the properties of the elements.
Chlorine is in the 17th period.Elements in the 17th period have 7 electrons in the outermost energy level. So chlorine has 7 electrons in the 3rd energy level.Chlorine has 17 electrons. It's electron configuration is [Ne] 3s2 3p5. Therefore it has 7 electrons in its third (outermost) energy level.
The row is called the period. Each element in the same period has the outermost electrons in the same shell (energy level). For example, the elements in the 3rd period all have the outermost electrons in the 3rd shell.
The group number 17 comprises of elements that has seven electrons in their own outer level.
aluminium
The valence electrons are the outer most electrons and the principal energy level in which they belong will vary for element to element and generally corresponds to the period number in which the element is present
No, energy levels and period numbers are different concepts in chemistry. Energy levels represent the different energy levels at which electrons can exist within an atom, while the period number indicates the shell in which the outermost electrons of an element reside. Each period corresponds to a different energy level, but not all elements in a period have electrons at the same energy level.
The periods in the periodic table tell you the energy level where the last electrons are being added. So, in period 1, the outermost electrons are in the first energy level or shell. In the 3rd period, the outermost electrons reside the the 3rd energy level, and so on.
An element's period is related to its electron configuration by indicating the energy level of its outermost electrons. Each period corresponds to a new energy level, with elements in the same period having electrons in the same principal energy level. Electron configuration describes the arrangement of electrons in these energy levels, with each period accommodating a specific number of electron shells.
The element's period indicates the number of energy levels or electron shells that its electrons occupy. Each period corresponds to a new energy level being filled by electrons. Moving from left to right across a period, the number of energy levels increases by one as you go from one element to the next.
Helium atoms only need 2 valence electrons to have a filled outermost energy level because helium is in the first period of the periodic table and its outermost energy level can only hold a maximum of 2 electrons.
They are in common because the number of valence electrons stay the same
Elements in the same grope share the same amount of energy shells, and valence electrons.
The period number of an element corresponds to the energy level of its outermost electrons. Elements in the same period have the same number of electron shells. As you move from left to right across a period, the number of protons and electrons increases, resulting in higher effective nuclear charge, which affects the properties of the elements.