Need if a chlorine atom were to gain one more electron, it would be similar to but not exactly the same as select one: a. argon b. bromine c. sulfur d. fluorine

- The correct answer is choice A, Argon.

Explanations:- Atomic number for chlorine atom is 17 means it has 17 electrons. If it gain one more electron then there becomes total 18 electrons.

Argon is next to chlorine and it's atomic number is 18 means it has 18 electrons. Chlorine ion and Argon atom has equal number of electrons means chlorine ion would be similar to Argon but not exactly the same as there is a difference of charge and number of protons.

  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-

pie chart because it is in percents ( % )