Zusammenfassung der Ressource
Bonding and Structure
- Types of Bonds
- Covalent Bonds
- It is a shared
pair of electrons
- Ionic Bonds
- It is the electrostatic
attraction between
oppositely charged
ions
- Metallic Bonds
- It is
electrostatic
attraction
between
positive metal
ions and
delocalised
electrons
- Types of Structures
- Giant Metallic Lattice
- It is a 3D structure of positive
ions and delocalised electrons bonded together
by strong metallic bonds.
- High melting point
- Lots of energy is
needed to break
the strong
metallic bonds
between
delocalised
electrons and
positive ions
- Conduct electricity
- The delocalised
electrons are
mobile i.e. free
to move and
carry current.
- Malleable and Ductile
- As the electrons in
the metallic lattice
are free to move, the
structure has a
degree to give, which
allows layers of
atoms to slide past
each other.
- Giant Ionic Lattice
- It is a 3D
structure
of
oppositely
charged
ions
bonded
together
by strong
ionic
bonds
- High Melting
Point
- Lots of
energy is
needed to
break stonng
electrostatic
attraction
between
oppositely
charged ions.
- Electrical conductivity
- Does not
conduct
when solid
- Ions in solids
have fixed
position and
hence are
not mobile
i.e. free to
move
- Conduct
when molten
or dissolved
- The ions
are mobile
and free
to move
to carry
current
- Soluble in
polar
solvents
- Water molecules attract Na+ and
Cl- ions in ionic lattice. Na+
attracts δ- charges on oxygen
atoms of the water molecule and
Cl- attracts δ+ charges on
hydrogen atoms of the water
molecules. The ionic lattice breaks
down as water molecules
surround the ions and dissolve it.
- Covalent Structures
- Giant Covalent Structure
- It is a 3D structure of atoms bonded
together by strong covalent bonds.
- High Melting Point
- Lots of energy is
needed to break the
strong covalent bonds
which are broken when
melting gian colvalent
lattice
- Does not conduct electricity
- There are no
charged particles
to carry current
- Insoluble
- The covalent bonds are
too strong to be broken
by wither polar or
non-polar solvents
- Simple molecule
- It is a 3D structure of molecules bonded
together by weak intermolecular forces.
- Low
Melting
Point
- Less energy is
needed to
break the weak
intermolecular
forces between
molecules.
- Three types of
weak
intermolecular
forces
- Van der
Waals' Forces
- It is the weak attractive forces
between induces dipoles of
neighbouring molecules
- Permanent
DIpole-Dipole
attraction
- It is the weak
attractive forces
between
permanent dipoles
of neighbouring
molecules
- Hydrogen
bonding
- It is the strong dipole-dipole attraction
between an electron-deficient hydrogen
atom on one molecule and the lone pair
of electrons on a highly electronegative
atom on a different molecule. (O/N/F)
- Do not
conduct
electricity
- No charged
particles free
to move and
carry current
- Soluble in
non-polar
solvent
- Weak Van Der Waal's
forces arise between
the non-polar
covalent molecules
and non-polar solvent
molecules. this
weakens the
structure and causes
it to break down.
- COVALENT BOND > METALLIC BOND > INTERMOLECULAR FORCES