Substances that exist in solution almost completely as ions are called strong electrolytes. Therefore, the answer is C.
We take activities of Solids and liquids equal 1. The reason is there concentrations not at all change amount of reactant at equilibrium in the reaction. Hence we don't consider concentrations of pure solids and liquids while writing equilibrium constant.
So for above reaction, equilibrium constant (K) = [Sn^2 +] ^3 x 1 / [Fe^3+]^2 x 1. Ping me if you have any doubts.
<h3>As fluorine sits atop chlorine in the periodic table, most people expect it to have the highest electron affinity, but this is not the case. ... Therefore, chlorine has a higher electron affinity than fluorine, and this orbital structure causes it to have the highest electron affinity of all of the elements.</h3>
The correct answer is:
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" F and Br , because they are in the same group" .
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Note:
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Choice [B]: "F and Br ; because they are in the same period" ; is incorrect; since "F" and "Br" are not in the same "period" (that is, "row").
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Choice [C]: "Na and Mg; because they are in the same group {"column"} ; is incorrect; since: "Na" and "Mg are NOT in the same group {"column"].
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Choice [D]: "Na and Mg" ; because they are in the same period {"row"}; is incorrect. Note: "Na" and "Mg" are, in fact, in the same period {"row"}. However, as aforementioned, {Mg and Na} are not in the same group {"column".}.
Note: The similiarities in physical and chemistry properties among elements are determined and organized — or tend to be so—by "groups" {"columns"} — NOT by "periods" {rows}.
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I believe it’s
The reactants
The products
And the Arrow indicating the direction of the chemical reaction