Problem 11 - Chemistry: The Central Science in SI Units, Global Edition

Question

Identify each of the following elements as a metal, nonmetal, or metalloid: (a) boron, (b) barium, (c) argon, (d) caesium, (e) yttrium, (f) astatine.

Step-by-Step Solution

Answer

(a) Boron: Metalloid, (b) Barium: Metal, (c) Argon: Nonmetal, (d) Caesium: Metal, (e) Yttrium: Metal, (f) Astatine: Nonmetal.

Step 1: Look up the elements in the periodic table

Before you can identify which category each element belongs to, you need to look up each element in the periodic table. The periodic table is organized in such a way that you can tell the type of an element by examining its position on the table.

Step 2: Identify each element as a metal, nonmetal, or metalloid based on their properties

After looking up each element in the periodic table, we can now identify them as metals, nonmetals, or metalloids based on the properties and their location on the periodic table. (a) Boron: Boron is a metalloid. It is found in Group 13 and Period 2 of the periodic table. Metalloids have a mix of metallic and nonmetallic properties. (b) Barium: Barium is a metal. It is located in Group 2 and Period 6 of the periodic table. Metals typically have a shiny appearance, are good conductors of heat and electricity, and are malleable. (c) Argon: Argon is a nonmetal. It is in Group 18 and Period 3 of the periodic table. Nonmetals are poor conductors of heat and electricity, and they do not have metallic luster. (d) Caesium: Caesium is a metal. It is located in Group 1 and Period 6 of the periodic table. Metals, as previously mentioned, have metallic luster, are good conductors of heat and electricity, and are malleable. (e) Yttrium: Yttrium is a metal. It is found in Group 3 and Period 5 of the periodic table. Yttrium has the properties typical of metals, such as metallic luster, good heat and electricity conductivity, and malleability. (f) Astatine: Astatine is a nonmetal. It is located in Group 17 and Period 6 of the periodic table. Nonmetals exhibit poor conductivity and lack the metallic luster present in metals. So, in summary, the classification of each element is as follows: - Boron: Metalloid - Barium: Metal - Argon: Nonmetal - Caesium: Metal - Yttrium: Metal - Astatine: Nonmetal

Key Concepts

Metals

Metals are elements that have certain common characteristics. They are predominantly located on the left side of the periodic table. Here are some notable features of metals:

• Shiny Appearance: Metals usually have a lustrous, reflective surface. This gives many metals a shiny appearance when polished.
• Conductivity: One of the most prominent features of metals is their ability to conduct electricity and heat efficiently. This makes them widely used in electrical wiring and cookware.
• Malleability: Metals can be hammered or rolled into thin sheets without breaking. This property is called malleability, which is very useful in manufacturing processes.
• Ductility: Similar to malleability, ductility allows metals to be drawn into wires.

Examples of metals include barium, caesium, and yttrium. These elements, along with many others, showcase the typical properties that make metals so versatile and useful in everyday applications like construction, electronics, and transportation.

Nonmetals

Nonmetals are found on the right side of the periodic table. They bring about an essential contrast to metals regarding their physical and chemical properties.

• Poor Conductivity: Nonmetals are typically poor conductors of heat and electricity. This property makes them good insulators.
• Non-lustrous: Unlike metals, nonmetals do not have a shiny luster. They can be found in various states: gases like argon, solids like sulfur, or even liquids like bromine.
• Brittleness: Many solid nonmetals are brittle, which means they will break or shatter rather than deform when subjected to pressure.
• Variety of Colors: Nonmetals can come in a wide range of colors, adding to the diversity of this group.

Examples such as argon and astatine are nonmetals. They play crucial roles in various fields such as chemical reactions and the study of atmospheric conditions.

Metalloids

Metalloids possess a fascinating mix of properties found in both metals and nonmetals, making them unique:

• Semi-Conductors: Metalloids, like silicon and boron, are known for their semi-conductor properties. They can conduct electricity better than nonmetals but not as effectively as metals.
• Intermediate Appearance: These elements have some metallic shine, but not as much as pure metals, giving them an intermediate appearance.
• Various Uses: Due to their unique position on the periodic table, metalloids are important in electronic and chemical industries. For instance, their semi-conductive nature makes them vital to the production of electronic devices.

Boron is a prime example of a metalloid. It enjoys applications ranging from detergents to fiberglass, demonstrating the versatility of metalloids. Each element in this category has adapted uses that capitalize on their unique properties, bridging the gap between metals and nonmetals.