Which of the sets of elements are not in order of increasing force of attraction on the outermost electron in atoms of that element? Ba < Sr < Ca
Al < P < Cl
F < Cl < Br
Mo < Pd < Sn

The elements that are not arranged in their increasing force of attraction base on the outermost electron present in their atoms is D:

Mo < Pd < Sn.

Therefore , option D is correct.

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The set of elements that are not arranged in the order of increasing ionization energy is Mo < Pd < Sn

Explanation:

The force of attraction on the outermost electron of an element can be described by the ionization energy of the element which decreases down a group and increases across a period

1) The given elements Ba, Sr, Ca, are group 2 elements arranged in the order from bottom up, which gives an increasing ionization energy, therefore;

Ba < Sr < Ca is arranged in increasing ionization energy, and therefore, increasing force of attraction of the outermost electron in atoms of the elements

Similarly, Al < P < Cl and Mo < Pd < Sn, are arranged in order of increasing ionization energy

However F < Cl < Br which are arranged from top down of elements in period 17 are arranged in the order of decreasing ionization energy, and therefore, decreasing force of attraction of the outermost electron in atoms of the elements.

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

increased stability in the completion of fluorine's outer shell.