Question

When zinc reacts with dilute hydrochloric acid, the gas evolved is:
A. hydrogen
B. chlorine
C. hydrogen chloride
D. none of these

Answer 1

In order to answer this question, first we will write the exact balanced reaction between zinc with dilute hydrochloric acid and then observe which gas is evolved during the reaction. We will discuss more about the given reaction.

Complete answer:
When Zn reacts with dilute $HCl$ , ${H_2}$ ​ gas is evolved.
Reaction:
$Zn + 2HCl \to ZnC{l_2} + {H_2}$
All compound changes include an exchange of energy. At the point when zinc responds with hydrochloric corrosiveness, the test tube turns out to be warm as energy is delivered during the response. Some different responses ingest energy. While energy changes are a likely indication of a substance response, care should be taken to guarantee that a compound response is undoubtedly occurring. Actual changes likewise include an exchange of energy.
The softening of a strong assimilates energy, while the buildup of gas discharges energy. The best way to be sure that a compound response has occurred is to test the synthesis of the substances after the change has occurred to check whether they are not quite the same as the beginning substances.
Hence the correct answer is option (A).

Note:
At the point when zinc responds with hydrochloric corrosiveness, the response bubbles enthusiastically as hydrogen gas is created. The creation of gas is likewise a sign that a synthetic response is happening.