When sodium is placed in water, it reacts vigorously, producing an explosion. This is due to the highly reactive nature of sodium and the exothermic reaction that takes place.
Here's a step-by-step explanation of why sodium creates an explosion when it comes into contact with water:
1. Sodium (Na) is an alkali metal, which means it belongs to a group of highly reactive elements. It has a single valence electron in its outermost shell, which it readily donates to other elements.
2. Water (H2O) is a polar molecule, meaning it has a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom. This polarity makes water an excellent solvent and facilitates chemical reactions.
3. When sodium is added to water, it reacts violently because it is highly reactive and reacts vigorously with water. The sodium atoms lose their outermost electron and form positively charged sodium ions (Na+).
4. The loss of an electron by sodium creates a highly unstable situation. To stabilize itself, the sodium ions react with water molecules.
5. During the reaction, the water molecules surrounding the sodium ions are attracted to the positive charge of the sodium ions. The water molecules surround the sodium ions and form a hydrated sodium ion complex (Na+(aq)).
6. The reaction between sodium and water is exothermic, meaning it releases heat energy. This heat energy further accelerates the reaction, causing a rapid increase in temperature.
7. The increase in temperature causes the water to vaporize, forming hydrogen gas (H2) and sodium hydroxide (NaOH). The hydrogen gas is highly flammable.
8. The rapid release of hydrogen gas, combined with the heat generated by the exothermic reaction, creates an explosion.
In summary, the explosion occurs because sodium is a highly reactive metal that reacts vigorously with water. The reaction is exothermic, releasing heat energy that vaporizes the water, forming hydrogen gas and sodium hydroxide. The rapid release of flammable hydrogen gas, combined with the heat generated, leads to an explosion.