Respuesta :

Mg gained mass because it went from being a single element (on the reactant side) to being a molecule (on the product side).

Mg element is gaining mass. Hence, option A is correct.

What is a chemical equation?

A chemical reaction is a representation of symbols of the elements to indicate the number of substances and moles of reactant and product.

Mg gained mass because it went from being a single element (on the reactant side) to being a molecule (on the product side).

Hence, option A is correct.

Learn more about chemical equations here:

https://brainly.com/question/12363199

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