Pls help ASAP A student was roasting marshmallows over a fire. The student noticed that the marshmallows turned brown, and they were
bubbling. Is this a chemical or physical change to matter? How do
you know? List two signs that you know what type of change it is.

A chemical change

Explanation:

The marshmallow turning brown and bubbling implies that a chemical change has taken place.

For chemical changes to occur, we observe any of the following:

ii. Two signs that shows a chemical change has taken place is that:

air quality

poor drinking water

and heavy polution

can lead to poor health

  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-