Concept:A reactive metal displaces hydrogen from a dilute acid, forming a metallic salt and liberating hydrogen gas.
Explanation:In this reaction, the metal atom donates electrons to the hydrogen ions in the acid.
This reduces the hydrogen ions to hydrogen atoms, which pair up to form diatomic hydrogen gas (
H2) that escapes as bubbles.
The metal cations simultaneously combine with the anions from the acid to produce a salt.
For example, when sodium reacts with hydrochloric acid:
2Na+2HCl→2NaCl+H2↑.
The compound
NaCl is the salt formed, while
H2 is the gas liberated.
This pattern holds true for other reactive metals, such as magnesium, zinc, and iron, with dilute acids like sulphuric acid or hydrochloric acid.
Thus, the only product formed alongside the liberated hydrogen gas is a salt.
Answer:A. Salt