Which statement describes a property that is unique to metalloids?
A Metalloids are shiny.
B Metalloids are semiconductive.
C Metalloids are solid.
D Metalloids are brittle.
The Correct Answer and Explanation is :
The correct answer is B: Metalloids are semiconductive.
Explanation:
Metalloids, also known as semimetals, are elements that have properties of both metals and nonmetals. They are located along the zigzag line on the periodic table, which separates metals from nonmetals. The defining property of metalloids is their semiconductivity, which means they can conduct electricity but not as efficiently as metals. This characteristic is crucial in many electronic devices, such as semiconductors, transistors, and microchips.
Why Option B is Correct:
Semiconductivity is the unique and distinguishing feature of metalloids. Unlike metals, which are good conductors of electricity, metalloids only conduct electricity under certain conditions, such as when their temperature is increased or when they are doped with other elements. This ability to control the flow of electricity makes metalloids essential in the electronics industry, where they are used to control electrical signals. Silicon, one of the most well-known metalloids, is the backbone of the computer chip industry.
Why the Other Options are Incorrect:
- A. Metalloids are shiny: While some metalloids, such as silicon and arsenic, may have a metallic luster, this property is not unique to them. Metals are typically shiny as well, so this does not distinguish metalloids from other elements.
- C. Metalloids are solid: Most metalloids are solid at room temperature, but this is not unique to them. Metals and some nonmetals (like iodine) are also solid at room temperature.
- D. Metalloids are brittle: Although some metalloids like silicon and germanium are brittle, others like arsenic and antimony can be more malleable or flexible. Brittleness is not a universal property of metalloids.
In summary, semiconductivity is the hallmark of metalloids, setting them apart from metals and nonmetals in terms of their electrical properties and their uses in technology.