Tin, because it has five energy levels with four electrons in the fifth level
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Explanation:
Tin has an electronic configuration as
1s2,2s2,2p6,3s2,...........4d10, 5s2,5p2
They have four valence electrons in their outer shell
Among the four diagrams given Tin is least reactive because the atomic radius of tin is largest among all four options. Due to large atomic radius electronegativity decreases and hence Tin is the least reactive element among Neon, Chlorine, gallium and tin.
The electronegativity of an element is its tendency to complete its octet by attracting electrons towards itself. Also tin is at the lowest place in the periodic table among all the four mentioned elements, its ionization energy is also low hence less electronegative and least reactive.
When a client comes into the emergency room (er) after hitting his head while playing any sport, if he is alert and oriented. immobilize the client´s head and neck would be a priority nursing intervention, because a head injury is treated as if a cervical spine injury is present until x-rays confirm their absence, then call for an immediate head computed tomography to look for any spine or head injury.
The answer is Heredity! :)
Would would would would would