Metal Reactivity with Water Explained
Understanding how metals react with water helps classify them. Metals have different reactivity levels based on their position in the reactivity series.
Reactivity of Sodium, Potassium, and Calcium
Sodium (Na) and Potassium (K) are alkali metals that react vigorously with cold water.
- Sodium reaction: $2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)$
- Potassium reaction: $2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)$
Calcium (Ca) reacts with cold water, but less intensely. It reacts more readily with hot water.
- Calcium reaction: $Ca(s) + 2H2O(l) → Ca(OH)2(aq) + H2(g)$
Aluminium's Lack of Reaction with Water
Aluminium (Al) does not react with cold or hot water under normal conditions. This is due to the formation of a protective, inert aluminium oxide ($Al2O3$) layer on its surface. This layer prevents water from contacting the metal.
While Aluminium reacts with steam at high temperatures ($2Al(s) + 3H2O(g) → Al2O3(s) + 3H2(g)$), it remains passive towards liquid water (cold or hot).
Similar Questions
- Metal oxides which react with acids as well as bases are called:
- Which of the following metals is found in free state?
Important Questions from Metals & Non-metals
- Which metals are generally used for electrical transmission lines?
- Which keyboard button is used as a shortcut to rename a selected file or folder in Windows?
- Which element from Group 17 is used to eliminate bacteria and viruses from surfaces, drinking water, sewage, industrial waste, and swimming pools and spas?
- Which copper-based alloy is a preferred material for making standard resistors because of its high resistivity and low temperature coefficient?
- Which of the following minerals is known for its insulating properties and is used in electrical industries?
