Understanding the Reaction of Magnesium with Hydrochloric Acid

Magnesium and Hydrochloric Acid Reaction:

Magnesium (Mg) reacts with hydrochloric acid (HCl) to produce hydrogen gas (H?) and magnesium chloride (MgCl?), as shown in the following chemical equation:

Chemical Equations and Reaction Steps

Equation 1: Reacting Magnesium with Hydrochloric Acid

Mg 2HCl → MgCl? H?

This reaction is a standard single displacement reaction, which falls under the category of oxidation-reduction reactions. In this process, the magnesium loses two electrons, resulting in the formation of magnesium ions (Mg2?), and two hydrogen ions (H?) gain one electron each to form hydrogen gas (H?):

The chloride ions (Cl?) from the HCl remain in solution, forming MgCl?aq.

Observations and Collecting Hydrogen Gas

The reaction between magnesium and hydrochloric acid is quite lively. When the magnesium ribbon is immersed in a solution of hydrochloric acid, visible bubbles of hydrogen gas are produced. This reaction can be observed in a laboratory setting, and the volume of hydrogen gas can be measured using the water displacement method.

As the reaction proceeds, the magnesium reacts with the acid, releasing hydrogen gas that can be collected and measured. A common method involves placing the magnesium ribbon in an aqueous solution of hydrochloric acid and capturing the released gas by displacement of water.

Advanced Observations

In an advanced setting, you can test the flammability of the collected hydrogen gas. If the flame of a butane fireplace lighter is held above the bursting bubbles of hydrogen gas, the bubbles will produce audible pops as the hydrogen gas ignites. This phenomenon highlights the flammability of hydrogen gas, which is a characteristic feature of this reaction.

It's important to note that magnesium is a reactive metal and hydrochloric acid is a corrosive liquid. Safety precautions should be observed during the experiment.

Further Considerations

When magnesium (Mg) reacts with hydrochloric acid (HCl), it forms magnesium chloride (MgCl?) and hydrogen gas (H?). The reaction is fairly simple and can be reversed:

Equation 2: Dissolution of Magnesium Chloride in Hydrochloric Acid

MgCl?aq 2HCl → Mg 2H?O

In this reaction, magnesium chloride in the solid form dissolves in water, forming magnesium ions (Mg2?) and chloride ions (Cl?) that mix with the hydrogen chloride ions (H?) and chloride ions (Cl?) already present in the aqueous solution.

Since there are no other substances present that can react to precipitate, the solution remains clear and no reaction occurs as described by:

MgCl?aq HClaq → no reaction

Conclusion: Magnesium and hydrochloric acid react to form magnesium chloride and hydrogen gas. This reaction can be observed and measured in a laboratory setting, making it an excellent example for understanding single displacement reactions and oxidation-reduction processes.