Which statement about the periodic table is true? a. Elements in the same column share similar properties.

b. Elements in the same row share similar properties.

c. Elements on the left have a larger nucleus than elements on the right.

d. Elements at the top of each column have the highest atomic mass in that column.

Statement that can be considered true as regards periodic table is : A: Elements in the same column share similar properties.

Therefore, option A is correct.

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Answer

Two different elements have similar chemical properties when they have the same number of valence electrons in their outermost energy level. ... Elements in the same column of the Periodic Table have the same number of valence electrons – that's why they have similar chemical properties.

  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-