$Zn + 2HCl \rightarrow ?$
The chemical reaction involves zinc (\(Zn\)), a reactive metal, and hydrochloric acid (\(HCl\)), an aqueous acid. This type of reaction is known as a single-replacement reaction, where a metal replaces a hydrogen atom in an acid to form a salt and hydrogen gas. Based on the standard oxidation states, zinc typically forms a \(2+\) ion (\(Zn^{2+}\)) and chlorine forms a \(1-\) ion (\(Cl^-\)). Therefore, to maintain electrical neutrality, the salt formed between zinc and chlorine is zinc chloride, represented by the chemical formula \(ZnCl_2\). Additionally, hydrogen is released as a diatomic molecule, \(H_2\).
The given equation is \(Zn + 2HCl \rightarrow ?\). We have established that the products are zinc chloride (\(ZnCl_2\)) and hydrogen gas (\(H_2\)). Balancing the atoms, we see that one atom of zinc reacts with two molecules of hydrogen chloride to produce one molecule of zinc chloride and one molecule of hydrogen gas. This results in the complete balanced chemical equation:
\[Zn + 2HCl \rightarrow ZnCl_2 + H_2\]
Comparing our result with the provided options:
The correct set of products is \(ZnCl_2 + H_2\). Therefore, the final answer is the third option.
This reaction is a classic example of how metals interact with acids. In everyday life, this principle is observed when cleaning metal surfaces or in industrial processes involving electroplating. For instance, if you were to place a piece of zinc into a solution of hydrochloric acid, you would observe bubbles of gas (hydrogen) forming and the metal slowly dissolving as it converts into zinc chloride. Understanding these reactions helps scientists predict outcomes when mixing various chemical substances safely and efficiently.