The law of conversion states that mass is never created or destroyed. Explain how this law requires all chemical equations to be balanced.

See Explanation

Explanation:

The Law of Conservation of Matter as applied to chemical reactions says that matter is neither created nor distroyed, only changed in form. This implies that the mass of substances going into a reaction process must equal the mass of products generated during the reaction process.

Empirically,

∑ mass reactants = ∑ mass products

One can test this idea after balancing a chemical equation by determining the sum of formula weights of reactants and products; then compare. If reaction was properly balanced, the total mass reactants = total mass of products.

Example:

Combustion of Methane =>  CH₄(g) + 2O₂(g)   =>  CO₂(g) + 2H₂O(l)

Equation Weights =>             16amu + 64amu <=> 44amu +  36amu

Mass Reactants = Mass Products  => 80amu <=> 80amu.

*amu = atomic mass units => sum of atomic weights of elements

the answers would be

the first one and the second one