Question

Which of the following is a correctly written chemical equation that demonstrates the conservation of mass? Responses Mg + HC1→H2+MgC12 Mg + HC1 → H 2 + MgC 1 2 H2O+CO2→H2CO3 H 2 O + C O 2 → H 2 C O 3 KC1O3→KC1 + O2 KC 1 O 3 → KC1 + O 2 H2+O2→H2O

Answer 1

A balanced chemical equation demonstrates the conservation of mass by having an equal number of each type of atom on both sides of the equation, such as in Mg + 2HCl → MgCl₂ + H₂. Mass is neither created nor destroyed in the process, and adjusting coefficients in equations ensures balance.

Step-by-step explanation:

The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction. A balanced chemical equation reflects this by having the same number of each type of atom on both sides of the equation. For instance, the balanced equation Mg + 2HCl → MgCl₂ + H₂ shows that mass is conserved with one magnesium atom, two hydrogen atoms, and two chlorine atoms participating in the reaction and the same numbers of each appearing in the products. This illustrates that the total mass of reactants equals the total mass of products. Other common practices to illustrate this principle include using precise measurements in a controlled reaction, like heating magnesium in a sealed container with oxygen to form magnesium oxide without altering the total mass.

When balancing equations, coefficients are adjusted to make the number of atoms of each element equal on both sides of the equation. For example, in the equation 2Hg + O₂ → Hg₂O₂, the coefficient '2' in front of Hg ensures that there are two mercury atoms on both sides. Similarly, coefficients are adjusted in the balanced equation C₂H₄ + 2O₂ → 2CO₂ + 2H₂O, to have an equal number of carbon, hydrogen, and oxygen atoms on both sides.