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Question 6 • Physical Science

Akia is balancing the equation Na+H2O→NaOH+H2. He tries to find the coefficients that will balance the equation. How could he find the correct coefficients?

Answer

by counting the total mass of each compound and making sure the reactants have more mass than the products

by counting the total atoms and making sure the number of atoms in the reactants is the same as the number of atoms in the products

by counting each individual atom and making sure the number of each kind of atom is the same in the reactants and the products

by counting the mass of each atom and making sure the reactants are more massive than the products

Explanation

Balance a chemical equation by making sure each type of atom appears the same number of times on both sides. For example, the equation must have equal numbers of sodium, hydrogen, and oxygen atoms among the reactants and products. Counting only the total number of atoms, as in choice B, is not enough because the kinds of atoms could differ. Therefore, the correct choice is counting each individual atom and matching each kind on both sides.

AI-written and checked against the verified answer.

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