When hydrochloric acid is mixed with magnesium and a flame is put in the tube what causes a reaction?
2HCl+ Mg >>> H2 + MgCl2
The reaction that occurs when hydrochloric acid is mixed with magnesium and a flame is put in the tube is a chemical reaction that produces hydrogen gas.
Hydrochloric acid (HCl) is a strong acid, capable of dissociating in water to release hydrogen ions (H+) and chloride ions (Cl-). Magnesium (Mg) is a reactive metal that readily reacts with acids. When magnesium is placed in hydrochloric acid, the following reaction takes place:
Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g)
In this reaction, the magnesium reacts with the hydrochloric acid to produce magnesium chloride (MgCl2) and hydrogen gas (H2). The hydrogen gas is given off as bubbles.
The flame that is put in the tube is used to ignite and burn the hydrogen gas produced in the reaction. When hydrogen gas reacts with oxygen in the presence of heat or flame, it undergoes combustion, resulting in the production of water (H2O). The reaction can be represented as:
2H2 (g) + O2 (g) → 2H2O (g)
So, the combination of the hydrochloric acid, magnesium, and the flame leads to the formation of magnesium chloride and the subsequent combustion of hydrogen gas.