Displacement of Hydrogen from Acid by Magnesium
Mg + 2HCl → MgCl2 + H2
Overview
Magnesium is oxidized from Mg⁰ to Mg²⁺ while hydrogen ions are reduced from H⁺ to H₂. This vigorous redox reaction produces rapid hydrogen evolution and significant heat. The reaction rate can be studied by varying acid concentration, temperature, or magnesium surface area.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Reactant | Magnesium Mg | 1 | (s) |
| Reactant | Hydrochloric Acid HCl | 2 | (aq) |
| Product | Hydrogen H | 1 | (g) |
Everyday Example
This reaction is commonly used in school chemistry labs to study reaction kinetics by measuring the rate of hydrogen gas evolution.
Industrial Importance
Understanding metal-acid redox reactions is fundamental to corrosion science, electrochemistry, and metallurgical processing.
Properties
- Type
- Redox
- Reversible
- No
- Energy
- Exothermic
- ΔH
- -462.0 kJ/mol
Related Reactions
Aqua Regia Dissolving Gold
Bleaching with Sodium Hypochlorite
Cerium(IV) Reduction by Iron(II)
Chlorine Oxidation of Bromide
Chromate-Dichromate Equilibrium
Contact Process SO₂ Oxidation
Copper Displaced by Iron
Copper Oxidation by Nitric Acid
Copper Patina Formation (Verdigris)
Copper Reduction of Silver Ion
Frequently Asked Questions
What is the equation for Displacement of Hydrogen from Acid by Magnesium?
The balanced equation is: Mg + 2HCl → MgCl₂ + H₂.
What type of reaction is Displacement of Hydrogen from Acid by Magnesium?
Displacement of Hydrogen from Acid by Magnesium is a redox reaction.
Is Displacement of Hydrogen from Acid by Magnesium exothermic or endothermic?
Displacement of Hydrogen from Acid by Magnesium is exothermic (releases energy). The enthalpy change (ΔH) is -462.0 kJ/mol.