You have just performed a laboratory activity where a lot of chemical waste was produced. all of the chemical wastes should be
a. taken home.
b. dumped down the sink.
c. left at the lab for the next class to handle.
d. disposed of according to your teacher's instructions.

The correct option is d

Explanation:

There are several ways of harmlessly disposing chemical wastes and as such some chemical wastes have special disposal methods (for example hazardous wastes such as inflammable wastes, corrosive wastes and poisonous wastes).

For the reasons above, it is necessary for the teacher's instruction to be followed in disposing the waste because the teacher will have a better knowledge of the class of waste and the best method to harmlessly dispose such waste (most especially because of the large waste produced) .

pla·gia·rism

/ˈplājəˌrizəm/

learn to pronounce

noun

the practice of taking someone else's work or ideas and passing them off as one's own.

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-