Uploaded August 2025 | Updated September 2026, 2 weeks ago
Properties of Metals, Nonmetals and Metalloids
Dr. DeBacco
Metals, Nonmetals and Metalloids Locations
Metals- Physical Properties Part 1
Luster: Shiny and reflective due to delocalized electrons that interact with light.
Malleability and Ductility: Can be shaped or drawn into wires because metallic bonds allow atoms to slide past each other without breaking.
High Electrical and Thermal Conductivity: Delocalized electrons move freely, conducting electricity and heat efficiently.
Metals- Physical Properties Part 2
High Melting and Boiling Points: Strong metallic bonding (electrostatic attraction between positive metal ions and a "sea" of delocalized electrons) requires significant energy to break, though this varies (ex. mercury has a low melting point).
High Density: Most metals are dense due to closely packed atoms.
Exceptions: alkali metals like sodium, potassium
Solid at Room Temperature: Most are solids, except mercury (liquid).
Metals- Chemical Properties
Form Positive Ions: Lose valence electrons easily due to low ionization energy
Form Basic Oxides: Metal oxides (ex. Na₂O) react with water to form bases or are insoluble.
High Electropositivity: Tendency to donate electrons in reactions, especially in Group 1 and 2 (alkali and alkaline earth metals).
Form Metallic Bonds: Strong attraction between metal cations and delocalized electrons.
Nonmetals- Physical Properties Part 1
Lack of Luster: Dull or non-reflective
Except iodine, which has a slight sheen
Brittle: Solid nonmetals (ex. sulfur) are brittle or crumbly, lacking malleability due to covalent bonding.
Poor Conductivity: Low electrical and thermal conductivity because electrons are localized in covalent bonds or molecular structures
Exception: graphite, a form of carbon, conducts electricity
Nonmetals- Physical Properties Part 2
Low Melting and Boiling Points: Many exist as gases (ex. O₂, Cl₂) or volatile solids (ex. S₈) due to weak intermolecular forces (ex. van der Waals forces), though covalent networks (ex. diamond) have high melting points.
Low Density: Often less dense than metals (exceptions: some solid nonmetals like iodine).
Varied States: Can be gases (ex. nitrogen), liquids (ex. bromine), or solids (ex. sulfur) at room temperature.
Non-Metals Chemical Properties
Form Negative Ions or Share Electrons: High electronegativity (due to high Zₑff) allows nonmetals to gain electrons (forming anions, Cl⁻) or share electrons in covalent bonds (O₂, Cl₂) or networks (diamonds).
Form Acidic or Neutral Oxides: Nonmetal oxides (CO₂, SO₂) often form acids when dissolved in water or are neutral (CO).
High Electronegativity: Strong tendency to attract electrons in bonds, especially halogens (Ex. Fluorine).
Metalloids- Physical Properties
Variable Luster: Often have a metallic sheen but may appear dull
Ex. Silicon looks metallic but is brittle
Brittle: Lack malleability and ductility, breaking like nonmetals when stressed.
Semiconductors: Intermediate electrical conductivity, which increases with temperature (unlike metals).
Moderate Melting and Boiling Points: Often high due to covalent network structures (Ex. Silicon’s melting point is 1410°C), but lower than metals in some cases.
Moderate Density: Densities are typically between those of metals and nonmetals.
Metalloids- Chemical Properties
Amphoteric Behavior: Can act as metals or nonmetals depending on conditions.
Example, their oxides (ex. SiO₂) may form weak acids or bases.
Form Covalent or Mixed Bonds: Tend to form covalent bonds (like nonmetals) but can exhibit some metallic characteristics in compounds.
Variable Electron Behavior: Can gain, lose, or share electrons, depending on the reaction, due to intermediate electronegativity and ionization energy.
Link to Lecture Slides: drive.google.com/file/d/1UfAg-J3ALo_tndnK3QvGNa-R_mqY1flJ/view?usp=drive_link
*Due to the description character limit the full work cited for "Properties of Metals Nonmetals and Metalloids" can be viewed at... docs.google.com/document/d/1okvs6CkJ4G_Ee-ACLhOeIjas80ixOuKu/edit?usp=drive_link&ouid=104237452697237972847&rtpof=true&sd=true
Properties of Metals, Nonmetals and Metalloids
Dr. DeBacco
Metals, Nonmetals and Metalloids Locations
Metals- Physical Properties Part 1
Luster: Shiny and reflective due to delocalized electrons that interact with light.
Malleability and Ductility: Can be shaped or drawn into wires because metallic bonds allow atoms to slide past each other without breaking.
High Electrical and Thermal Conductivity: Delocalized electrons move freely, conducting electricity and heat efficiently.
Metals- Physical Properties Part 2
High Melting and Boiling Points: Strong metallic bonding (electrostatic attraction between positive metal ions and a "sea" of delocalized electrons) requires significant energy to break, though this varies (ex. mercury has a low melting point).
High Density: Most metals are dense due to closely packed atoms.
Exceptions: alkali metals like sodium, potassium
Solid at Room Temperature: Most are solids, except mercury (liquid).
Metals- Chemical Properties
Form Positive Ions: Lose valence electrons easily due to low ionization energy
Form Basic Oxides: Metal oxides (ex. Na₂O) react with water to form bases or are insoluble.
High Electropositivity: Tendency to donate electrons in reactions, especially in Group 1 and 2 (alkali and alkaline earth metals).
Form Metallic Bonds: Strong attraction between metal cations and delocalized electrons.
Nonmetals- Physical Properties Part 1
Lack of Luster: Dull or non-reflective
Except iodine, which has a slight sheen
Brittle: Solid nonmetals (ex. sulfur) are brittle or crumbly, lacking malleability due to covalent bonding.
Poor Conductivity: Low electrical and thermal conductivity because electrons are localized in covalent bonds or molecular structures
Exception: graphite, a form of carbon, conducts electricity
Nonmetals- Physical Properties Part 2
Low Melting and Boiling Points: Many exist as gases (ex. O₂, Cl₂) or volatile solids (ex. S₈) due to weak intermolecular forces (ex. van der Waals forces), though covalent networks (ex. diamond) have high melting points.
Low Density: Often less dense than metals (exceptions: some solid nonmetals like iodine).
Varied States: Can be gases (ex. nitrogen), liquids (ex. bromine), or solids (ex. sulfur) at room temperature.
Non-Metals Chemical Properties
Form Negative Ions or Share Electrons: High electronegativity (due to high Zₑff) allows nonmetals to gain electrons (forming anions, Cl⁻) or share electrons in covalent bonds (O₂, Cl₂) or networks (diamonds).
Form Acidic or Neutral Oxides: Nonmetal oxides (CO₂, SO₂) often form acids when dissolved in water or are neutral (CO).
High Electronegativity: Strong tendency to attract electrons in bonds, especially halogens (Ex. Fluorine).
Metalloids- Physical Properties
Variable Luster: Often have a metallic sheen but may appear dull
Ex. Silicon looks metallic but is brittle
Brittle: Lack malleability and ductility, breaking like nonmetals when stressed.
Semiconductors: Intermediate electrical conductivity, which increases with temperature (unlike metals).
Moderate Melting and Boiling Points: Often high due to covalent network structures (Ex. Silicon’s melting point is 1410°C), but lower than metals in some cases.
Moderate Density: Densities are typically between those of metals and nonmetals.
Metalloids- Chemical Properties
Amphoteric Behavior: Can act as metals or nonmetals depending on conditions.
Example, their oxides (ex. SiO₂) may form weak acids or bases.
Form Covalent or Mixed Bonds: Tend to form covalent bonds (like nonmetals) but can exhibit some metallic characteristics in compounds.
Variable Electron Behavior: Can gain, lose, or share electrons, depending on the reaction, due to intermediate electronegativity and ionization energy.
Link to Lecture Slides: drive.google.com/file/d/1UfAg-J3ALo_tndnK3QvGNa-R_mqY1flJ/view?usp=drive_link
*Due to the description character limit the full work cited for "Properties of Metals Nonmetals and Metalloids" can be viewed at... docs.google.com/document/d/1okvs6CkJ4G_Ee-ACLhOeIjas80ixOuKu/edit?usp=drive_link&ouid=104237452697237972847&rtpof=true&sd=true
