Properties of Metals Quiz

Metal Characteristics

• Metals comprise about 80% of the periodic table elements
• Metallurgy, the study of metals, dates back to 6000 BC, beginning with gold.
• Metals have diverse physical and chemical properties making them crucial in daily life.

Physical Properties of Metals

• Metal atoms typically have 1, 2, or 3 valence electrons
• Metal bonding, known as metallic bonding, involves a "sea" of delocalized, mobile electrons surrounding positive metal cations.
• The strong electrostatic attraction between the positive metal ions and the delocalized electrons holds the metal lattice together.
• Metals generally have high melting and boiling points due to the strong forces of attraction between positive metal ions and negative electrons.
• Metals are excellent conductors of heat and electricity due to the delocalized electrons that are free to move.

High Melting and Boiling Points in Metals

• Electrostatic forces of attraction between positive metal cations and negative electrons are very strong.
• Consequently, significant heat energy is needed to overcome these forces and melt or boil the metal.
• All metals, except mercury, are solids at room temperature.

Malleability and Ductility in Metals

• Metals are malleable meaning they can be hammered and bent into different shapes.
• Metals are ductile, meaning they can be drawn out into wires.
• The atoms in the metal are all the same size and type, allowing the layers to slide over each other without breaking the metallic bonds when force is applied.

High Densities in Metals

• Density is the mass of a substance divided by its volume.
• Metal atoms are tightly packed together in a metal lattice, leading to high densities in metals.

Metal Reactions with Oxygen

• Some metals react readily with oxygen, others do not.
• Reactivity determines how quickly it reacts with oxygen.
• The reaction of metals with oxygen forms metal oxides, which are ionic compounds.
• Potassium, sodium, calcium, and magnesium react very quickly with oxygen and must be stored carefully.

Metal Reactions with Water

• Highly reactive metals react violently with cold water, forming metal hydroxides and hydrogen gas.
• Some metals react slowly with water or not at all, but react with steam.
• Potassium, sodium, and calcium react more vigorously with water, producing flames.

Metal Reactions with Steam

• Less reactive metals, such as magnesium, react slowly with cold water, but quickly with steam, producing metal oxides and hydrogen.

Metal Reactions with Dilute Acids

• Most reactive metals react vigorously with dilute acids(excluding nitric acid), producing a salt and hydrogen gas.

Decomposition of Metal Compounds

• Many metal compounds decompose when heated.
• Examples include metal nitrates, carbonates, and hydroxides.
• Heating metal nitrates results in their decomposition into a metal oxide, nitrogen dioxide, and oxygen.
• Heating metal carbonates results in their decomposition into the corresponding metal oxide and carbon dioxide.
• Heating metal hydroxides results in their decomposition to the corresponding metal oxide and water.