Physical properties
1) Physical state – Metals are solids at room temperature e.g. sodium, aluminum ,potassium, magnesium. There are exception to this. Mercury and gallium are metals but they are in liquid state at room temperature.
2) Luster – Metals have a shining surface called luster when freshly prepared. They have a quality of reflecting light from their surface and they can be polished e.g. metals like gold, silver, copper show this property.
3) Malleability – Metals can be beaten into thin sheets. This property is called malleability. Due to this property, metals can be rolled into sheets e.g. aluminum, copper, zinc can be beaten into sheets.
4) Ductility – Metals can be drawn into thin wires. This property is called ductility. For example, 100 grams of silver can be drawn into a thin wire about 200 meters long.
5) Hardness – Metals are generally hard e.g. iron, cobalt, nickel. There are few exceptions to this. Sodium and potassium are soft and they can be cut with a knife.
6) Conduction – Generally, metals are good conductors of heat and electricity because they have free electrons. Silver and copper are the two best conductors . Relatively, lead and bismuth are poor conductors of heat and electricity.
7) Density – Metals generally have high density and they are heavy. Iridium and osmium have the highest densities while lithium has the lowest density.
8) Melting and boiling point – Metals usually have high melting point and boiling point. For example, iron, cobalt and nickel have high melting and boiling point. Tungsten has the highest melting point. There are some exceptions to this. For example , most of the alkali metals have low melting and boiling point.
9) Tensile strength – Most of the metals possess high tensile strength i.e. tenacity. For example, iron, titanium, some alloys have high tensile strength. However, elements like sodium, potassium and mercury do not possess tenacity.
Chemical properties of metals
1) Electron configuration – Metals usually have 1 to 3 electrons in the outermost shell of their atom. For example, sodium, magnesium and aluminum have 1, 2 and 3
electrons respectively in the outermost shell of their atom.
2) Valency – Metal atoms can lose 1 to 3 electrons in their outermost shell and show valencies1 to 3.
3) Electrochemical nature – Metal atoms have tendency to lose electrons and form cations.
4) Electronegativity – Metals generally have low electronegativity i.e. tendency to attract electrons in the state of molecule.
5) Formation of oxides – Metals form oxides which are generally ionic and basic in nature. If this basic oxide dissolves in water, it forms an alkali. For example, oxides of Na, K and Ca viz. Na2O, K2O and CaO are highly basic in nature and when dissolved in water, they form alkalies NaOH, KOH and Ca(OH)2.
6) Reducing agent – All metals act as reducing agents.
