Lana balanced an equation so that the result was 2c2h3br + 5o2 → 4co2 + 2h2o + 2hbr. which most likely represents the starting equation?
2c4h3br + 5o2 → 4co2 + 2h2o + 2hbr
c2h3br + 5o2 → 4co2 + h2o + 2hbr
c4h3br + o2 → co2 + h2o + hbr
c2h3br + o2 → co2 + h2o + hbr

The correct option is option D which is C2H3Br + O2 → CO2 + H2O + HBr.

chemists can use the electron cloud model to assign electrons to different atomic orbitals. atomic orbitals also explain the patterns in the periodic table

explanation:

  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-