Which equation illustrates the law of conservation of mass?

Responses

4NH3 + 5O2 -> 4NO + 6H2O
4NH 3 + 5O 2 -> 4NO + 6H 2 O

SiO2 + HF -> SiF4 + 2H2O
SiO 2 + HF -> SiF 4 + 2H 2 O

NaOH + CO2 -> Na2CO3 + H2O
NaOH + CO 2 -> Na 2 CO 3 + H 2 O

Al + FeO -> Al2O3 + Fe