Which one of the following is not a metalloid?

A. Boron

B. Silicon

C. Gallium

D. Germanium

To determine which of the options listed is not a metalloid, we first need to understand what metalloids are. Metalloids are elements that have properties intermediate between metals and non-metals. They typically exhibit a mix of characteristics, such as being semiconductors of electricity and having a metallic luster. The common metalloids include boron, silicon, germanium, arsenic, antimony, and tellurium.

Analyzing the Options

Let’s take a closer look at each of the options provided:

• A. Boron: This element is indeed a metalloid. It has properties that are characteristic of both metals and non-metals, making it a classic example of a metalloid.
• B. Silicon: Silicon is another well-known metalloid. It is widely used in electronics due to its semiconducting properties.
• C. Gallium: This is where we find our answer. Gallium is classified as a metal, not a metalloid. It has a metallic structure and exhibits typical metallic properties, such as being malleable and ductile.
• D. Germanium: Like boron and silicon, germanium is also a metalloid. It shares similar properties and is used in semiconductor technology.

Conclusion

From the analysis above, it is clear that the element that is not a metalloid is C. Gallium. It stands out from the others due to its classification as a metal, while boron, silicon, and germanium are all metalloids. Understanding these classifications helps in grasping the broader concepts of the periodic table and the properties of elements.