When pbi2 is added to na2co3 a white precipitate is formed. the white precipitate most likely is?

The white precipitate formed is of lead carbonate having formula

Explanation:

When lead iodide reacts with sodium carbonate, it leads to the formation of a white colored precipitate of lead carbonate along with sodium iodide.

This reaction is a type of double displacement reaction in which exchange of ions takes place.

The equation for the above reaction follows:

Hence, the white precipitate is of lead carbonate.

  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-