Tin, because it has five energy levels with four electrons in the fifth level
.
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.
<span>Biomes are defined as the world's major communities, classified according to the predominant vegetation and characterized by adaptations of organisms to that particular environment.</span>
Yearly dental visits are a part of good dental hygiene because the dentist will check for cavities, fix them, clean your teeth very thoroughly (or whitening treatment), and check the progress and movement of your teeth. They can also recommend when dental surgery is necessary, for instance, if you have extra teeth that can be removed or when your wisdom teeth are coming in. Hope this helps! :)