Reaction Equation:
Ca(s) + 2HNO₃(aq) → Ca(NO₃)₂) (aq) + H₂(g) + Heat
Explanation:
1. Calcium (Ca) is oxidized: Calcium metal loses electrons to form calcium ions (Ca²⁺).
2. Nitric acid (HNO₃) is reduced: The hydrogen ions (H⁺) from nitric acid gain electrons to form hydrogen gas (H₂).
3. Calcium nitrate (Ca(NO₃)₂) is formed: Calcium ions (Ca²⁺) react with nitrate ions (NO₃⁻) from the acid to form calcium nitrate, a soluble salt.
4. Hydrogen gas (H₂) is released: Hydrogen gas is produced as a byproduct of the reaction and is released as bubbles.
5. Heat is released: The reaction is exothermic, meaning it releases heat and makes the solution hot.
Additional Notes:
* Side Reactions: Nitric acid can further react with the hydrogen gas produced, leading to the formation of nitrogen oxides (NOx) as well. This is particularly likely if the concentration of nitric acid is high.
* Safety: The reaction is highly exothermic and can be dangerous if not handled with care. Always wear appropriate safety gear, such as gloves and goggles, and work in a well-ventilated area.
Overall: The reaction between calcium and nitric acid is a classic example of a single displacement reaction, where a more reactive metal (calcium) displaces a less reactive element (hydrogen) from its compound. The reaction results in the formation of calcium nitrate, hydrogen gas, and the release of heat.
