Activity Series: Remembering the Reactivity of Metals

Activity series or reactivity series of metals explain certain properties of metals, mainly the reactivity of metals. In the series, elements on the top are more reactive than those at the bottom. The reactivity of these metals is usually determined by their ability to form positive ions. The more reactive a metal is, the more likely it is to lose electrons and form a positive ion.

The activity series can help predict if a single displacement reaction will occur. For example, if a metal higher in the activity series reacts with a compound containing a metal lower in the series, a single displacement reaction will occur. The more reactive metal will displace the less reactive metal from a compound.

Moreover, this activity series describes the loss of electrons (oxidation potential), corrosive nature, and energy required for metal extraction processes from the ores. It is important to note that this activity series is not absolute and can vary slightly depending on the specific conditions of the reaction.

What is the activity of metal exactly?

The activity of metals is defined by their ability to lose electrons and become ions. Some metals are more reactive than others because of their electronic configuration. Alkali metals have one outermost electron so they can lose their electron to gain a stable configuration. The activity of alkali metals increases down the group. The reason is the additional shell makes farther the leaving electron. This means that the metals with more than one electron in the outermost shell are more reactive than the ones having just one electron.

For example, zinc is more reactive than copper. Therefore it can replace the copper from the CuSo₄ solution and become Zn²⁺.

The significant features of the activity series

The activity series places metals in order of their tendency to participate in chemical reactions. Some prominent outcomes of the activity series are given below:

• Everything above hydrogen in the list can displace hydrogen from its acid.
• Hydrogen cannot reduce oxides of metals present above it in the series.
• Highly reactive metals can react with cold water.
• Less reactive metals will not react even with hot water.
• It also explains why aluminum forms a protective (insoluble) layer of aluminum oxide (Al₂O₃) and seems unreactive.

Applications and uses of activity series of metals

1. Metals reaction with water

The reaction of metals with water can be predicted with activity series of metals. The topmost metals react vigorously with water to liberate hydrogen gas. On going down the activity series, the tendency of metals to react decreases. For example, at room temperature zinc does not react with water but above 50ºC it reacts, and hydrogen bubbles are witnessed.

2. Metals displacement reactions

Activity series of metals can be used to predict metal displacement. For example, reactive metals are added to the solution of less reactive metals for extraction purposes.

3. Hydrogen gas

Hydrogen gas is liberated when reactive metals come in contact with mineral acids.

Key Point: Remember the common members of the activity series this way:

Additional Resources

• Coinage metals
• Conduction of metals
• Atomic Radius

Concepts Berg

Which metal is the least reactive?

Platinum is the least reactive metal. Its stability is due to the fine arrangements of metal ions and electrons in its structure. That is why it is frequently used at extremely high temperatures.

Are non-metals reactive or non-reactive?

Non-metals are usually less reactive but some of them are very reactive. The reactivity of nonmetals is based on the ability to gain electrons to complete the octet. The halogens, for instance, require only one electron to complete their octet, therefore these are the most reactive of all non-metals

Which is more reactive Zn or Pb?

Zinc (Zn) is present above in the activity series form lead (Pb). So, it is more susceptible to losing electrons than lead. Thus, zinc is more reactive.

Which metal has the highest reactivity?

Cesium (Cs) is the most reactive metal in the periodic table. The reactivity of metal depends upon the oxidation potential (ability to lose electrons). In this case, cesium has a single electron in its outermost shell. Moreover, the effective nuclear charge on that electron is the least due to the presence of five electronic shells between the nucleus and the electron. Therefore it will readily lose the electron.

Which series is the most reactive series?

The activity series of metals describes the relative reactivity of metals against the standard hydrogen. This series has metal atoms arranged from higher reactivity to lower reactivity.

Why is knowledge of the activity series for metals important?

Activity series of metals is essential in predicting the double displacement reactions. Metallurgists also apply the same principle during the extraction of metals.

References

• https://www.thoughtco.com/activity-series-of-metals-603960/