Answer:
The transition elements have their valence electrons in two different sets of orbitals that are (n-1)d and ns. Thus, transition elements show variable valencies due to the involvement of penultimate d shell electrons.
Explanation:
The dark colored moths are beneficial in a polluted area because they have a lesser chance of being eaten since they blend into the trees polluted with soot.
<span>Dichotomous </span><span>Key Is One Approach To Identify Something Unknown?
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