Periodic Properties of the Elements

Metals, Nonmetals and Metalloids


Metals, Nonmetals and Metalloids

Characteristic properties of metallic and non-metallic elements:

Metallic Elements

Nonmetallic elements

Distinguishing luster (shine)

Non-lustrous, various colors

Malleable and ductile (flexible) as solids

Brittle, hard or soft

Conduct heat and electricity

Poor conductors

Metallic oxides are basic, ionic

Nonmetallic oxides are acidic, compounds

Cations in aqueous solution

Anions, oxyanions in aqueous solution

Metals

Metal oxide + water -> metal hydroxide

Na2O(s) + H2O(l) -> 2NaOH(aq)

CaO(s) + H2O(l) -> Ca(OH)2(aq)

Metal oxide + acid -> salt + water

MgO(s) + HCl(aq) -> MgCl2(aq) + H2O(l)

NiO(s) + H2SO4(aq) -> NiSO4(aq) + H2O(l)


Al has 3+ charge, the oxide ion is O2-, thus Al2O3

Oxides of metals are characteristically solid at room temp

Metal oxide + acid -> salt + water

Al2O3(s) + 6HNO3(aq) -> 2Al(NO3)3(aq) + 3H2O(l)


Nonmetals

    1. H2(g)
    2. N2(g)
    3. O2(g)
    4. F2(g)
    5. Cl2(g)
    6. Br2(l)
    7. I2(l) (volatile liquid - evaporates readily)

Nonmetal + Metal -> Salt

3Br2(l) + 2Al(s) -> 2AlBr3(s)

Nonmetal oxide + water -> acid

CO2(g) + H2O(l) -> H2CO3(aq) [carbonic acid]

(carbonated water is slightly acidic)

Nonmetal oxide + base -> salt

CO2(g) + 2NaOH(aq) -> Na2CO3(aq) + H2O(l)

Metalloids

Properties intermediate between the metals and nonmetals.

Silicon for example appears lustrous, but is not malleable or ductile (it is brittle - a characteristic of some nonmetals). It is a much poorer conductor of heat and electricity than the metals. Metalloids are useful in the semiconductor industry.

Trends in Metallic and Nonmetallic Character


1996 Michael Blaber