What are metals? Physical Properties of Metals

• Prepared by Sir Patrick

What are Metals?

• Metals naturally form as minerals or substances below the Earth's surface.
• Most metals are lustrous, exhibiting shininess.
• Metals are inorganic, meaning they originate from non-living substances.
• Metals are found in the Earth's crust as natural compounds, forming metal ores with other elements.
• Metals exist in rocks washed by water and in atmospheric dust.

Physical Properties

• Physical properties of metals include shininess, malleability, ductility, and conductivity.
• A malleable material can be hammered or rolled into sheets and shapes.
• A ductile material can be drawn into a long wire.
• Copper is an example of a metal that can be made into thin sheets and wire due to its malleability and ductility.
• Conductivity is an object's ability to transfer heat or electricity.
• Most metals are good conductors.
• Iron (Fe), cobalt (Co), and nickel (Ni) are a few magnetic metals that are attracted to magnets and can be made into magnets.
• Most metals are solid at room temperature.
• Mercury (Hg) is a liquid at room temperature.

Chemical Properties

• Reactivity is the ease with which an element combines or reacts with other elements.
• Metals usually react by losing electrons.
• Some metals are very reactive like sodium (Na), which reacts strongly with air or water.
• Sodium and similarly reactive metals must be stored under oil in sealed containers to prevent reactions.
• Gold (Au) and platinum (Pt) are valued for their lack of reactivity and their rarity.

Metals in the Periodic Table

• Metals in the same group or family share similar properties, with gradual changes across the table.
• Metal reactivity decreases from left to right across the periodic table.

Alkali Metals

• Group 1 metals, from lithium to francium, are known as alkali metals.
• Alkali metals react by losing one electron.
• Alkali metals are too reactive to be found in nature as uncombined elements, existing only in compounds.
• Scientists can isolate pure alkali metals in the laboratory.
• As pure elements, some alkali metals are shiny and soft enough to be cut with a plastic knife.
• Sodium and potassium are the most important alkali metals.
• Sodium compounds are abundant in seawater and salt beds.
• Diets need compounds of sodium and potassium.
• Lithium is used in batteries and some medications.

Alkaline Earth Metals

• Alkaline earth metals are found in Group 2 of the periodic table.
• Each alkaline earth metal is fairly hard, gray-white, and a good conductor of electricity.
• They react by losing two electrons.
• Alkaline earth metals are less reactive than Group 1 metals, but more reactive than most others.
• The Group 2 metals, like Group 1, are never found uncombined in nature.
• Magnesium and calcium are the two most common alkaline earth metals.
• Magnesium mixed with aluminum creates strong yet lightweight material used in various products like ladders and vehicle parts.
• Calcium compounds are vital for teeth and bones.
• Calcium aids in muscle function.
• Calcium is obtained from dairy and green, leafy vegetables.

Transition Metals

• Groups 3 through 12 elements are known as transition metals.
• Transition metals include familiar metals such as iron, copper, nickel, silver, and gold.
• Most transition metals are hard and shiny.
• All transition metals are good conductors of electricity.
• Many transition metals create colorful compounds.
• Transition metals are less reactive than metals in Groups 1 and 2.
• The lack of reactivity accounts for the preserved state of ancient gold coins and jewelry over time.
• Iron reacts with air and water to form rust, a process that may take many years.
• Some transition metals, like iron, are vital for health.
• Iron forms hemoglobin which carries oxygen in the bloodstream.
• Transition metals can be very colorful such as Cadmium, Zinc, Chromium, and Cobalt and are used to make paints.

Metals in Mixed Groups

• Only some elements in Groups 13-15 of the periodic table are metals.
• These metals are less reactive than those on the left side of the table.
• Aluminum, tin, and lead are the most familiar of these metals.
• Aluminum is a lightweight metal for beverage cans and airplane bodies.
• A thin coating of tin prevents steel corrosion in canned foods.
• Lead was formerly used in paints but is poisonous so its common use is in automobile batteries and weights for balancing tires.