Molecular Covalent Compunds, Ionic Compounds, Hydrogen Bonds

Chemistry : Molecular Covalent Compunds, Ionic Compounds, Hydrogen Bonds
Molecule
Molecules form when two or more atoms form chemical
bonds with each other. It doesn't matter if the atoms
are the same or are different from each other.
O2, H2, N2
H2O, CO2, CH4
Compound
A compound (which is a molecule) where two or more DIFFERENT atoms join together chemically, with covalent or ionic bonds. CO2, H2O, CH4
Ionic Compond
In chemistry, an ionic compound is a chemical compound
in which ions are held together in a lattice structure by ionic
bonds. The positively charged ions are called cations and
the negatively charged ions are called anions.
between
metals
non-metals
electron transfer
ions formed
+ve cation
-ve anions
electostatic forces of attraction
giant structure
lattice
solid (room temperature)
not conduct electricity
dissolve in water
aqueous state
conduct electricity
high melting point
high boiling point
Covalent (Molecular) Compound
structure
giant compound
covalent bonds
giant structure
high boiling point
silicon
water
hydrogen bonds
molecular covalent compound
2/3 elements
covalent bonds
intermolecular forces
weak
low melting point
low boiling point
dependent upon elements
between
non-metals
electon sharing
bad conductors of electricity
if at all
EXCEPT GRAPHITE
hexagonal planes
sea of electrons between layers
delocalised electrons
carbon
state
usually
liquid
gas
brittle
good insulators of heat
covalent bonds
Hydrogen Bonding
special case of intramolecular bonding
highly electro negative atoms
Oxygen
Flourine
Nitrogen
bond polarity
difference between
electronegativity
ability to attract negative charge
electrons
between bond atoms
chemical bond
region occupied by electrons
electrons in constant motion
between nuclei
high electropositive bonded
to high electronegative
electrons
more time near electronegative
build up of charge
less time near electropositve
electron deficient
build up positive charge
polar molecule
partial charges
electrostatic attraction
molecules pack close together
hard to separate
hydrogen
donates electron
becomes positive charge in space
attracts anion
O, N, F
hold electrons close to nucleus
high polar bonds
Hydrogen Bond
electrostatic attraction
hydrogen atom
lone pair of electrons
not true bonds
aggregate of atoms
stuck together by attractive forces
water
hydrogen bond
molecules "stick" together
free ions
good solvent
partial charges
oxygen partial negative
hydrogen partial positve
liquid
attractive forces
cohesion
water beads on a surface
attractive forces between atoms
adhesion
attraction to other things
glass (SiO2)
O attracted to ions in glass
freezing
polar charge
repel
expand
inter or intra molecular bonds
Water is a polar molecule, and its intramolecular
bonds are polar covalent. To put it simply, the
bonding is covalent, and not ionic, because both
hydrogen and oxygen are nonmetals (at standard
temperature and pressure). It is a polar molecule
because of its molecular shape and because of the
disparity in the electronegativities of hydrogen and
oxygen. In fact, because hydrogen is so much less
electronegative than oxygen, there is a strong
intermolecular force known as hydrogen bonding
present in water. Hydrogen bonding is an exceptional
case of dipole-dipole interactions.
Intermolecular - Hydrogen bonding (we can see there's an H and the Oxygen.
Intramolecular: covalent; nonmetals
int_ER_molecular Forces
Intermolecular forces are forces of attraction or repulsion
which act between neighboring particles (atoms, molecules or ions).
They are weak compared to the intramolecular forces, the
forces which keep a molecule together.
e.g covalent bonds of HCl are stronger
than bonds between the molecules
forces between molecules
relatively weak
2 or more molecules
Hydrogen Bond
is this intERmolecular as the bond polarity
causing hydrogen bond is between molecules.
int_RA_molecular Forces
An intramolecular force is any force that holds together
the atoms making up a molecule or compound.[1]
They contain all types of chemical bond. They are
stronger than intermolecular forces, which are present
between atoms or molecules that are not actually bonded.
Hydrophobic Interactions
Ionic Bonds
metal + nonmetal
Covalent Bond
nonmetal + nonmetal
Metalic
delocalised electrons
forces within molecules
one molecule
covalent bonds between O & H in water?
strong forces
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