Question

Which equation obeys the law of conservation of mass?

Answer 1

Explanation:

According to law of conservation of mass, total mass of reactants will be equal to the total mass of products.

For example, $HCl + NaOH \rightarrow NaCl + H_{2}O$

Therefore, mass of reactant molecules will be as follows.

Mass of HCl is 36.46v g/mol

Mass of NaOH is 39.99 g/mol

Total mass of reactants is (36.46 + 39.99) g/mol = 76.45 g/mol

Mass of product molecules will be as follows.

Mass of NaCl is 58.44 g/mol

Mass of $H_{2}O$ is 18.01 g/mol

Total mass of products is (58.44 + 18.01) g/mol = 76.45 g/mol

Thus, we can conclude that any equation which represents total mass of reactants equal to the total mass of products is actually obeying the law of conservation of mass.

Answer 2

4Fe + 3O2 → 2Fe2O3, hope this helps man!