Helium has the electron configuration 1s2
Beryllium.
The element with the electron configuration 1s2 2s2 2p6 is neon.
1s2 2s2 2p2
5 electrons: 1s2 2s2 2p1, so an uncharged atom would have 5 protons: Boron.
This element is chlorine (group 17).
Element 27 Cobalt.
There are a total of 14 electrons in this electron configuration. The element whose atomic number corresponds to 14 is silicon.
The element with the electron configuration 1s2 2s2 2p6 is neon.
Magnesium, Mg
1s2 2s2 2p2
Magnesium
Magnesium
Magnesium
5 electrons: 1s2 2s2 2p1, so an uncharged atom would have 5 protons: Boron.
This element is chlorine (group 17).
Element 27 Cobalt.
The electron configuration of 1s2 2s2 2p5 is for the element fluorine. Fluorine is a corrosive and poisonous gas. It has an atomic number of 9 and its group number is 17.
Aluminium.