Conservation of mass for the reaction below?
4na(s) + o2(g) → 2na2o(s)

Explanation:

According to law of conservation of mass, mass can neither be created nor it can be destroyed. It can only be changed from one form to another.

Basically, mass is conserved in a chemical reaction.

For example,  

Mass of given reactants is as follows.

4Na = = 92 g/mol

= 32 g/mol

Total mass of reactants = (92 + 32) g/mol = 124 g/mol

Mass of product is as follows.

2 =

                 = 124 g/mol

Therefore, we can conclude that mass of reactants is equal to the mass of products. Hence, mass is conserved.

answer carbon and three oxygen atoms;