Question

Which of the following equation does not obey law of conservation of mass?

CH4 + 2O2à CO2 + 2H2O
Zn + HCl à ZnCl2 + H2
Zn + H2SO4à ZnSO4 + H2
Na + HCl à NaCl + H2

Answer 1

Zn + HCl —> ZnCl2 + H2

Na + HCl —> NaCl + H2

Step-by-step explanation:

The law of conservation of matter (mass) states that matter can neither be created nor destroyed during a chemical reaction, but can be transferred from one form to another.

A balanced chemical reaction support the law of conservation of matter (mass) as the total number of atoms on the right side equals the total number of atoms on the left side.

An unbalanced equation shows that atoms are either created or destroyed.

Conserdering the equations above, the following are unbalanced:

Zn + HCl —> ZnCl2 + H2

Na + HCl —> NaCl + H2

Therefore, it will not obey the law of conservation of mass.