Reactivity series is an arrangement of metals from highest to lowest reactivity order. Therefore, the term “reactivity series of metal” refers to a series of metals arranged in descending order of reactivity. It is also known by the name “activity series.” The reactivity of metals is due to their electronic structure or to the incomplete outer orbitals. As they tend to lose electrons, metals produce positively charged ions. High atomic number metals are more likely to be reactive since their electrons can be withdrawn with ease because they are separated from the positively charged nucleus.
What is the Reactivity Series?
It has been observed that some metals react quickly and strongly with reactants, while others react slowly, or some do not react at all. This is because of the reactivity of the metal. Here, reactivity means the ability of a chemical substance to give the product on its own.
The arrangement of metals in a series of decreasing order of their tendencies to react is called the Reactivity Series of metal. Therefore, the least reactive metal (Platinum) is placed at the bottom while, the highly reactive metal (Potassium) is at the top of this series.
To determine if a metal can displace another in a single displacement reaction, the data provided by the reactivity series can be utilized. It can also be used to find out how reactive various metals are to acids and water.
Below is a chart showing the reactivity series of common metals:
Salient Features of Reactivity Series
- The reducing tendency of metals at the top of the table has high, that is why they are easily oxidized. These metals can get tarnished or corrode very easily.
- The electro-positivity (tendency to lose electrons) of the elements gets reduced while moving down the reactivity series of metals.
- The tendency to reduce the metals becomes weaker while traversing down the series.
- On reaction with dilute HCl or dilute H2SO4, all metals that are found above hydrogen in the activity series liberate H2 gas.
- Higher ranking metals require greater amounts of energy for their isolation from ores and other compounds.
Long Tabular Form of the Reactivity Series
The Reactivity series of some of the most common metals, arranged in descending order of reactivity:
React with Cold Water
Reacts very slowly with cold water, whereas quickly in boiling water, and very strongly with acids.
Reacts with steam and acids
Reacts with concentrated mineral acids
Reacts with acids
May react with some strong oxidizing acids
React slowly with water
Highly unreactive May react with some of the strong oxidizing acids
Important uses of Reactivity Series
The reactivity series provides the study of properties and reactivities of the metals, Apart from this reactivity series also provides several other important applications. For example, the result we get out of the reactions between metals and acids, metals and water, and single displacement reactions between metals can be predicted.
- Reaction Between Metals and Water: Calcium and the metals that are more reactive than calcium in the reactivity series can react with cold water to form the corresponding hydroxide while liberating hydrogen gas. For example, the reaction between potassium and water yields potassium hydroxide and H2 gas, as described by the chemical equation provided below.
2K + 2H2O → 2KOH + H2
- Reaction with Acid and bases: Metals, displace hydrogen from its dilute acids which are more reactive than hydrogen, and form respective metal salts and hydrogen gas.
Metal + dilute acid → Salt + Hydrogen gas
- Sodium metal has a tendency to displace hydrogen from hydrogen chloride (HCl) to form sodium chloride and liberate hydrogen gas. the reaction is given below:
2Na(s) + 2HCl (dilute) → 2NaCl (aq) + H2(g)
Tricks to Remember Reactivity Series of Metals
The basic strategy for learning the reactivity series is to group these elements into meaningful groups and then use a mnemonic for each group.
Here we have uses the sentence “Please send charlie’s monkeys and zebras in lead & hydrogen cages in mountains securely guarded by Plato.” The first letter of each word represents a metal of the reactivity in the order from highest to lowest as:
Metal of the Reactivity Series
Words/Mnemonic used to Remember the Series
FAQs based on the Reactivity Series of Metals
Question 1: What is the reactivity series of metals?
The arrangement of metals in a series of decreasing order of their tendencies to react is called the Reactivity Series of metal.
Question 2: What does a reactivity series show?
Reactivity series shows a list of metals arranged based on their tendencies to react from highest to lowest order. This implies that the most reactive metals are at the top while the least reactive metals at the bottom.
Question 3: Which is the most reactive metal?
According to the reactivity series of metals, Potassium (K) is the highly reactive metal.
Question 4: Which metal is the least reactive?
According to the reactivity series of metals, Platinum (Pt) is the least reactive metal.
Question 5: What does the reactivity series of metals depend on?
The reactivity of metals is determined by its reactivity, which is influenced by the atomic radius, nuclear charge, arrangement of the sublevel electrons, and shielding effect.
Please Login to comment...