Properties metal and non metals

 Metal and Non-Metals Notes

Physical Properties

Physical Properties of Metals

● Hard and have a high tensile strength

● Solid at room temperature

● Sonorous

● Good conductors of heat and electricity

● Malleable, i.e., can be beaten into thin sheets

● Ductile, i.e., can be drawn into thin wires

● High melting and boiling points (except Caesium (Cs) and Gallium (Ga))

● Dense, (except alkali metals). Osmium – highest density and lithium – least density

● Lustrous

● Silver-grey in colour, (except gold and copper)

Non-Metals

Nonmetals are those elements which do not exhibit the properties of metals.

Physical Properties of Non-metals

• Occur as solids, liquids and gases at room temperature

• Brittle

• Non-malleable

• Non-ductile

• Non-sonorous

• Bad conductors of heat and electricity

Exceptions in Physical Properties

• Alkali metals (Na, K, Li) can be cut using a knife.

• Mercury is a liquid metal.

• Lead and mercury are poor conductors of heat.

• Mercury expands significantly for the slightest change in temperature.

• Gallium and caesium have a very low melting point.

• Iodine is non-metal but it has lustre.

• Graphite conducts electricity.

• Diamond conducts heat and has a very high melting point.

Chemical Properties

Chemical Properties of Metals

● Alkali metals (Li, Na, K, etc) react vigorously with water and oxygen or air.

● Mg reacts with hot water.

● Al, Fe and Zn react with steam.

● Cu, Ag, Pt, Au do not react with water or dilute acids.

How Do Metals and Nonmetals React

Metals lose valence electron(s) and form cations.

Non-metals gain those electrons in their valence shell and form anions.

The cation and the anion are attracted to each other by strong electrostatic force, thus forming an ionic bond.

For example: In calcium chloride, the ionic bond is formed by opposite charged calcium and chloride ions.

Calcium atom loses 2 electrons and attains the electronic configuration of the nearest noble gas (Ar). By doing so, it gains a net charge of +2.

The two Chlorine atoms take one electron each, thus gaining a charge of -1 (each) and attain the electronic configuration of the nearest noble gas (Ar).