Which chemical equation is balanced to show that mass is conserved during the reaction?
A.Na+Cl -> NaCl
B.2H2 O2 -> CO2+2H2 O + O2
C.CH4+O2 -> CO2+2H2 O
D.AgNO3+MgCl2 -> AgCl+MgNO3
C. CH4 + 2O2 -> CO2 + 2H2O
To determine which chemical equation is balanced to show that mass is conserved during the reaction, you need to check if the equation satisfies the law of conservation of mass. According to this law, the total mass of the reactants should be equal to the total mass of the products in a chemical reaction.
Let's analyze each option:
A. Na + Cl -> NaCl
This equation represents the formation of sodium chloride. However, it is not balanced because the number of atoms on both sides of the equation is different. There is one atom of sodium (Na) on the left side but only one atom of chlorine (Cl) on the right side. Therefore, this equation does not satisfy the law of conservation of mass.
B. 2H2 O2 -> CO2 + 2H2 O + O2
This equation represents the combustion of hydrogen peroxide. It is balanced because the number of atoms on both sides of the equation is the same. There are four hydrogen (H) atoms, four oxygen (O) atoms, and one carbon (C) atom on both sides. Therefore, this equation satisfies the law of conservation of mass.
C. CH4 + O2 -> CO2 + 2H2 O
This equation represents the combustion of methane. It is balanced because the number of atoms on both sides of the equation is the same. There are four hydrogen (H) atoms, two oxygen (O) atoms, and one carbon (C) atom on both sides. Therefore, this equation satisfies the law of conservation of mass.
D. AgNO3 + MgCl2 -> AgCl + MgNO3
This equation represents a double displacement reaction. It is balanced because the number of atoms on both sides of the equation is the same. There is one silver (Ag) atom, one nitrogen (N) atom, three oxygen (O) atoms, one magnesium (Mg) atom, and two chlorine (Cl) atoms on both sides. Therefore, this equation satisfies the law of conservation of mass.
Based on the analysis, options B, C, and D are balanced chemical equations that show the conservation of mass during the reaction.