FORMING METAL CATIONS
Only the outer shell electrons are lost in reactions. So metals found in the 1st, 2nd and 3rd (13th) shells will have a charge of +1, +2 and +3.
The charges on transition metal cations can vary due to the filling of the d shell.
TRANSITION METALS
•Have an unfilled d sub-shell
•Most transition metals are silver in colour and are similar in appearance.
•Some important transition metals include: Iron, nickel, silver, gold, copper.
•Transition metal compounds can be highly coloured.
In comparison to other metals in the periodic table, transition metals:
•Tend to be harder and denser
•Have higher melting points
•Some are magnetic (Iron, Nickel and Cobalt).
•Generally smaller sized atoms due to high core charge- so can pack closer together leading to harder, more dense metals.
METALLIC BONDING
•Metallic lattice structures are made up of an array of cations. The outer shell electrons from each metal atom are found in a common sea and are free to move between all the cations. These electrons are called delocalized electrons.
•Electrostatic forces of attraction between the positively charged cations and the negatively charged electrons hold the lattice together. This type of bonding is called metallic bonding.
Image- wikimedia commons
PROPERTIES OF METALS
•Important properties of metals include:
–are good conductors of heat and electricity ( charged particles, electrons, are free to move).
–have a range of melting points but most are quite high.
–are malleable.
–are ductile.
–are often hard (do not break easily)
–generally have high densities.
–are lustrous (have a shiny surface when polished).
Only the outer shell electrons are lost in reactions. So metals found in the 1st, 2nd and 3rd (13th) shells will have a charge of +1, +2 and +3.
The charges on transition metal cations can vary due to the filling of the d shell.
TRANSITION METALS
•Have an unfilled d sub-shell
•Most transition metals are silver in colour and are similar in appearance.
•Some important transition metals include: Iron, nickel, silver, gold, copper.
•Transition metal compounds can be highly coloured.
In comparison to other metals in the periodic table, transition metals:
•Tend to be harder and denser
•Have higher melting points
•Some are magnetic (Iron, Nickel and Cobalt).
•Generally smaller sized atoms due to high core charge- so can pack closer together leading to harder, more dense metals.
METALLIC BONDING
•Metallic lattice structures are made up of an array of cations. The outer shell electrons from each metal atom are found in a common sea and are free to move between all the cations. These electrons are called delocalized electrons.
•Electrostatic forces of attraction between the positively charged cations and the negatively charged electrons hold the lattice together. This type of bonding is called metallic bonding.
Image- wikimedia commons
PROPERTIES OF METALS
•Important properties of metals include:
–are good conductors of heat and electricity ( charged particles, electrons, are free to move).
–have a range of melting points but most are quite high.
–are malleable.
–are ductile.
–are often hard (do not break easily)
–generally have high densities.
–are lustrous (have a shiny surface when polished).