2. The first inert gas to be isolated was argon, in 1894. Argon was found to have an atomic weight of slightly less than 40. Which of the following proposed changes to
Mendeleev's original periodic table were supported by the properties of argon?
I. Calcium should no longer be considered one of the alkaline earth metals.
II. Another group of elements should be added to the periodic table.
III. Argons atomic weight is greater than Potassium, thus the periodicity of the elements
should depend on atomic number rather than atomic weight.

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Answerthe half-reaction having the greatest tendency to occur at the anode:     i₂(aq) + 2e⁻  ⇄ 2i⁻  ;   e = +0.53 v======oxidation occurs at the anode. we must therefore find the half-reaction with the greatest tendency to oxidize.the given values of e are reduction potentials (the form of the half-reactions are of reduction).the lower the reduction potential, the higher the potential to oxidize. the half-cell with the lowest reduction potential will have the greatest tendency to oxidize at the anode.the half-reaction having the greatest tendency must be    i₂(aq) + 2e⁻  ⇄ 2i⁻    e = +0.53 vbecause its reduction potential is the lowest out of the three.