Difference Between Transition Metals and Metalloids

The key difference between transition metals and metalloids is that the transition metals are chemical elements having atoms with unpaired d electrons whereas metalloids are chemical elements having their properties between metals and nonmetals.

Transition metals are essentially metallic elements. But, not all metals are transition metals because it has to fulfil the fact that atoms have unpaired d electrons for an atom to become a transition metal. On the other hand, metalloids are not metal or nonmetals. However, they have chemical and physical properties that lie between metals and nonmetals.

CONTENTS

1. Overview and Key Difference
2. What are Transition Metals
3. What are Metalloids
4. Side by Side Comparison – Transition Metals vs Metalloids in Tabular Form
5. Summary 

What are Transition Metals?

Transition metals are chemical elements having atoms with unpaired d electrons. At least, the stable cations they form should have unpaired d electrons. Furthermore, most of the d block elements are transition metals. However, we do not consider scandium and zinc as transition metals. That is because, they do not have any unpaired electrons even in their stable cations. These atoms have d electrons, but all of them are paired electrons.

Besides, transition metal elements can form different compounds with a variety of colours. That is mainly because, these elements can have different oxidation states which are very colourful. These different oxidation states of the chemical element can have different colours. And, these colours arise due to d-d electronic transitions. Moreover, due to the presence of these unpaired electrons, these metals are either paramagnetic or ferromagnetic. Almost all these elements can bond with ligands to form coordination complexes.

What are Metalloids?

Metalloids are the chemical elements having their properties in between metals and nonmetals. Most of the times, they have a mixture of the properties of metals and nonmetals. There are six common metalloids;

• Boron
• Silicon
• Germanium
• Arsenic
• Antimony
• Tellurium

Typically, these elements have a metallic appearance. But they are very brittle and are poor electrical conductors. When considering their chemical nature, they mostly relate to nonmetals rather than metals. Other physical properties are intermediate to metals and nonmetals. These chemical elements are important in the production of alloys, biological agents, catalysts, glasses, etc. More importantly, we can use them in the production of semiconductors, especially silicon and germanium.

These metalloids mainly exist in solid phase and are lustrous. They have intermediate ionization energies, and the electronegativity values lie round 2.0. When considering their oxide forms, they are amphoteric or weakly acidic.

What is the Difference Between Transition Metals and Metalloids?

Transition metals are chemical elements having atoms with unpaired d electrons whereas metalloids are the chemical elements having their properties between metals and nonmetals. This is the key difference between transition metals and metalloids. Another difference between transition metals and metalloids is that the transition metals have metallic properties and are highly electrically conductive when compared to metalloids because, the metalloids are common as semiconductors due to their intermediate ability to conduct electricity.

One other property that gives rise to a difference between transition metals and metalloids is the hardness. Typically, transition metals have a high hardness while metalloids are more brittle. Importantly, the chemical nature of metalloids relates to nonmetals rather than metals while transition metals have general chemical properties of metals.

The below infographic tabulates the difference between transition metals and metalloids in more detail.

Summary – Transition Metals vs Metalloids

Transition metals are a subcategory of metals. Metalloids are intermediate chemical elements to that of metals and nonmetals according to their chemical and physical properties. The key difference between transition metals and metalloids is that the transition metals are chemical elements which have atoms with unpaired d electrons whereas the metalloids are chemical elements having their properties in between metals and nonmetals.

Reference:

1. “Transition Metal.” Wikipedia, Wikimedia Foundation, 6 Oct. 2018. Available here 
2. “Metalloid.” Wikipedia, Wikimedia Foundation, 6 Oct. 2018. Available here  

Image Courtesy:

1.”Coloured-transition-metal-solutions”By No machine-readable author provided (Public Domain) via Commons Wikimedia  
2.”Semiconductor-1″By Lejla peace – Own work, (CC BY-SA 3.0) via Commons Wikimedia