Reactivity Series of Metals

Reactivity series is the ranking of metals according to their reactivity from highest to lowest.
The list of metals in the reactivity series from most reactive to least reactive is: Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Carbon, Zinc, Iron, Tin, Lead, Hydrogen, Copper, Silver, Gold, Platinum.
Potassium, sodium, lithium, and calcium are highly reactive metals. They react with cold water to produce hydrogen and a metal hydroxide.
Magnesium is a moderately reactive metal. It reacts with steam to produce hydrogen and a metal oxide. It will not react with cold water.
Aluminium and zinc are relatively unreactive with cold water but will react with steam.
Iron, tin, and lead do not react with water or steam but will react over time with oxygen in the air to form rust or tarnish.
Copper, silver, gold and platinum are unreactive and are found in the Earth as metal ores or sometimes pure metals.
Using a more reactive metal to displace a less reactive metal from its compound is called a displacement reaction.
Electrolysis is used to extract the most reactive metals from their ores.

Prediction of Metal Reactions

The reactivity series can be used to predict reactions between metals and acids, water or oxygen.
Highly reactive metals like potassium and sodium react violently with acids, producing hydrogen gas and a salt.
Less reactive metals like iron, zinc, and copper react more slowly with acids.
Unreactive metals such as gold and platinum do not react with acids or oxygen.
Exposure to water and oxygen causes corrosion in many metals, the rate of which depends on the metal’s position in the reactivity series.

Knowledge of the reactivity series is used in the process of extracting metals from their ores.
It helps in the selection of metals for specific purposes based on their reactivity.
Reactive metals are used in batteries due to their ability to transfer electrons.
Unreactive metals are used for jewellery and coating because of their resistance to rust and corrosion.
However, the high reactivity of some metals makes them hazardous and should be handled with care, especially potassium and sodium.
Unreactive metals often come at a higher cost due to their rarity and difficulty in extraction.

Blast furnaces are used to extract iron from its ore using carbon, based on the principle of displacement in the reactivity series.
Electrolysis is applied to extract reactive metals such as aluminium, sodium, and potassium from their ores.
Less reactive metals like copper, silver, and gold are extracted from their ores by heating them in air, a process known as roasting.
Recycling metals has many benefits: it saves energy, reduces landfill, conserves resources, and reduces the need for mining.