Question

which parts must be balanced in a chemical equation? (1 point) numbers of reactant and product atoms energy on the reactant and product sides numbers of reactant and product molecules states of reactants and products

Explanation:

To balance a chemical equation, we follow the law of conservation of mass, which states that matter is neither created nor destroyed in a chemical reaction. This means the number of each type of atom on the reactant side (left) must equal the number on the product side (right).

• The "energy on the reactant and product sides" is related to enthalpy changes (like exothermic/endothermic reactions) and not the balancing of the equation's atom counts.
• The "numbers of reactant and product molecules" can vary as we use coefficients to balance atoms, and molecule counts are adjusted to achieve atom balance, not the other way around.
• The "states of reactants and products" (like solid, liquid, gas, aqueous) are descriptive of the substances' physical states and do not affect the balancing of atoms.

So the correct part to balance is the numbers of reactant and product atoms.

Answer:

A. numbers of reactant and product atoms