Problem 20 - Chemistry for Allied Health

Question

Identify each of the following elements as a metal, nonmetal, or metalloid. a. iron (Fe) b. gallium (Ga) c. phosphorus (P) d. potassium (K) e. neon (Ne) f. germanium (Ge)

Step-by-Step Solution

Answer

Iron (Fe), gallium (Ga), and potassium (K) are metals. Phosphorus (P) and neon (Ne) are nonmetals. Germanium (Ge) is a metalloid.

Step 1: Understand the Question

We are asked to categorize elements into metals, nonmetals, or metalloids based on their position in the periodic table.

Step 2: Locate Iron on the Periodic Table

Iron (Fe) is found in Group 8, Period 4 of the periodic table. It is a strong, durable metal commonly used in construction and manufacturing.

Step 3: Categorize Iron

Iron (Fe) is categorized as a metal.

Step 4: Locate Gallium on the Periodic Table

Gallium (Ga) is located in Group 13, Period 4 of the periodic table. It has properties similar to metals and is found to the left of the metalloid line.

Step 5: Categorize Gallium

Gallium (Ga) is categorized as a metal.

Step 6: Locate Phosphorus on the Periodic Table

Phosphorus (P) is found in Group 15, Period 3 of the periodic table. It's an essential element for life and is nonmetallic in nature.

Step 7: Categorize Phosphorus

Phosphorus (P) is categorized as a nonmetal.

Step 8: Locate Potassium on the Periodic Table

Potassium (K) is located in Group 1, Period 4. As an alkali metal, it is highly reactive and essential in biology.

Step 9: Categorize Potassium

Potassium (K) is categorized as a metal.

Step 10: Locate Neon on the Periodic Table

Neon (Ne) is found in Group 18, Period 2. It's a noble gas, nonreactive and commonly used in lighting.

Step 11: Categorize Neon

Neon (Ne) is categorized as a nonmetal.

Step 12: Locate Germanium on the Periodic Table

Germanium (Ge) is in Group 14, Period 4. It has characteristics intermediate between metals and nonmetals and is found near the metalloid line.

Step 13: Categorize Germanium

Germanium (Ge) is categorized as a metalloid.

Key Concepts

Metals

Metals are elements that exhibit specific properties that make them very important in various applications. They are usually found on the left and the center of the periodic table and can be recognized by certain characteristics.

• Luster: Metals have a shiny appearance. This property makes them attractive for use in jewelry and decoration.
• Malleability: Metals can be hammered or rolled into thin sheets. This is why metals are used to make items like foils and sheets.
• Conductivity: They are excellent conductors of heat and electricity, which is why metals like copper are used in electrical wires and cookware.
• Ductility: Many metals can be drawn into wires without breaking. This property is essential for creating electrical cables.
• Reactivity: Some metals react with other elements. For example, iron reacts with oxygen to form rust.

Examples of metals include: - Iron (Fe): Known for its strength and durability, it's commonly used in construction. - Gallium (Ga): Although it appears similar to metals, it can melt in your hand, demonstrating unique physical properties. - Potassium (K): As an alkali metal, it is highly reactive, especially with water.

Nonmetals

Nonmetals reside primarily on the right side of the periodic table. They display a range of unique characteristics that differentiate them significantly from metals.

• Insulators: Nonmetals are generally poor conductors of heat and electricity, making them ideal as insulators.
• Variety of States: They can exist in different states at room temperature, such as solids (carbon), liquids (bromine), or gases (neon).
• Brittle: Nonmetals that are solids tend to be brittle and will shatter if struck.
• Lack of Luster: Unlike metals, nonmetals generally do not have a shiny appearance.
• Chemical Reactions: Nonmetals often form acids when combined with oxygen and hydrogen.

Here are some nonmetal examples: - Phosphorus (P): An essential element in biology, found in DNA and bones. - Neon (Ne): A noble gas used in colorful lighting, it is nonreactive due to its full valence electron shell.

Metalloids

Metalloids have properties that are intermediate between metals and nonmetals, making them highly versatile. They appear as a staircase on the periodic table, having a mix of both metalliferous and non-metallic properties.

• Semi-Conductors: Metalloids like silicon are used in the electronics industry due to their ability to conduct electricity under certain conditions.
• Appearance: They often have a metallic luster, making them look similar to metals.
• Variability: Some metalloid properties can be influenced by external pressure or temperature changes.
• Behavior in Reactions: They can behave like metals in some chemical reactions and nonmetals in others, depending on the conditions.

An example of a metalloid is: - Germanium (Ge): It exhibits semiconductor properties, making it valuable in optical applications and electronics.