4d7 , 3s2 will be the valence shell electronic configuration of a neutral atom of cobalt!
I, D, B, E, H, C, J, F, A, G, K
Answer:
chemical equilibrium, condition in the course of a reversible chemical reaction in which no net change in the amounts of reactants and products occurs. A reversible chemical reaction is one in which the products, as soon as they formed, react to produce the original reactants.
Explanation:
chemical equilibrium is the state in which both reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system.
Here are the CORRECT names and molecular formulas
carbonate:

bicarbonate:

Choice 1 is incorrect
nitrite:

nitrate:

Choice 2 is incorrect
sulfite:

sulfide:

Choice 3 is incorrect
By process of elimination, you can infer choice 4 is correct.
Actually, choice 4 is the only choice that displays the correct name and formula.
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