Which of the following elements is a metalloid?
neon
selenium
mercury
silicon
The correct answer and explanation is:
Correct Answer: Silicon
Explanation:
Among the elements listed — neon, selenium, mercury, and silicon — the metalloid is silicon.
What is a Metalloid?
Metalloids are elements that have properties of both metals and nonmetals. They often act as semiconductors and are located on the stair-step line between metals and nonmetals in the periodic table. This unique placement gives them characteristics that allow them to be used in technology, especially in electronics and computer chips.
Why Silicon is a Metalloid:
- Location: Silicon (Si) is found in Group 14 and Period 3 of the periodic table, right on the “metalloid line.”
- Properties: It has a metallic luster and is brittle like nonmetals. It conducts electricity, but not as well as metals — a classic trait of metalloids.
- Uses: Silicon’s ability to act as a semiconductor makes it essential in electronic devices like computers and smartphones.
What About the Others?
- Neon (Ne):
- A noble gas.
- Nonmetal.
- Inert and does not conduct electricity under normal conditions.
- Selenium (Se):
- A nonmetal, though sometimes shows limited metalloid behavior.
- Used in photocopiers and glassmaking.
- However, it is typically classified as a nonmetal.
- Mercury (Hg):
- A metal.
- The only metal that is liquid at room temperature.
- Used in thermometers and barometers (though less now due to toxicity concerns).
Conclusion:
Silicon is the correct answer because it displays a mix of metallic and nonmetallic properties, qualifying it as a metalloid. It plays a vital role in the modern tech industry due to its semiconducting abilities.