Question

Zinc + Hydrochloric acid$$\to$$
A. Zinc chloride + Hydrogen
B. Zinc + chlorine + Hydrogen
C. Zinc + Hydrogen
D. Zinc

Answer 1

Hint: Dilute hydrochloric acid (HCl) reacts with active metals to produce their respective chlorides and hydrogen gas.
The standard reaction is given as:
Metal + HCl (dil.)$$\to$$ Metal chloride + Hydrogen (g)

Complete Solution :
Zinc is an active metal, listed above hydrogen in the electrochemical series. Hence, zinc can easily displace hydrogen from HCL to form salt with chlorine.
From the general equation mentioned above, we can see active metals react with HCl (hydrochloric acid) to form the respective metal chloride and hydrogen gas.
Therefore, the balanced chemical equation of HCl reacting with zinc (Zn) can be written as:
$$\text{Zn +2 HCl}\to \text{ZnC}{\text{l}}_{\text{2}}\text{+ }{\text{H}}_{\text{2}}(g)$$

- In this reaction, hydrogen is reduced from a cation into the elemental form and zinc is oxidized from the elemental form into a cation.
The word equation is given by:
Zinc + Hydrochloric acid $$\to$$ Zinc chloride + Hydrogen
So, the correct answer is “Option A”.

Note: 1. The reaction of zinc with hydrochloric acid is known as a single-displacement reaction where zinc metal displaces the hydrogen to form zinc chloride (a salt) and hydrogen gas. Only those elements which are listed above hydrogen in the reactivity series can displace hydrogen in a chemical reaction.
2. The reaction of zinc with hydrochloric acid is accompanied by some physical changes in it. These physical changes include release of gas bubbles and increase in temperature.