Write formulas for the following compounds consisting of two non-metals or a metalloid and a non-metal.
(1)- hydrochloric acid
(2) hydro-sulfuric acid
(3)-hydro-iodic acid
(4)- silicon tetrafluoride
(5)-arsenic penta-fluoride
(6)-xenon hexafluoride
(7)-iodine penta-fluoride
(8)-krypton difluoride
(9)-tetra-sulfur tetra-nitride
(10)-dichlorine hepta-oxide
(11)-phosphorus trihydride (phosphine)
(12)- tetra-phosphorus decoxide

Explanation:

1) HCl

2) H₂S

3) HI

4) SiF₄

5 ) AsF₅

6) XeF₆

7 ) IF₅

8 ) KrF₂

9 ) S₄N₄

10) Cl₂O₇

11) PH₃

12) P₄O₁₀

  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-