GEN CHEM 2 Flashcards
Forces exist within molecules
Intramolecular Forces
Forces exist between molecules
Intermolecular Forces
Types of Intramolecular Forces
- Ionic Bond
- Covalent Bond
- Metallic Bond
- A bond that is formed by the complete transfer of valence electron(s) between atoms.
- a chemical bond that generates two oppositely charged ions.
- Non-metal + Metal
Ionic Bond
- formed between atoms that have similar
electronegativities. - Both atoms have similar affinity for electrons
- Non-metal + Non-metal
Covalent Bond
- formed via the attraction of
the mobile electrons - the sea of electrons
- and the fixed positively charged
metal ions. - Metal + Metal
Metallic Bond
Who is the first ferson that introduced intermolecular forces?
He did not develop but he was the first one who postulated the forces.
Johannes Diderik van der Waals
- The strongest intermolecular force.
- It exists between oppositely charged ions.
- Ions of like charges repel while opposite charges
attract.
Ion-Ion Forces
- a force that results from the electrostatic attraction between an ion and a neutral molecule that has a dipole.
- Occurs between a fully charged ion and
a partially charged dipole.
Ion-Dipole Forces
- a relatively strong force of attraction between molecules, and considerable energy is required to break its bonds.
- bonded to either an oxygen, nitrogen, or fluorine atom.
- Responsible for the unusually high boiling
point and the melting point of water.
Hydrogen Bonding
forces occur when the partially positively charged part of a molecule interacts with the partially negatively charged part of the neighboring molecule.
Dipole-Dipole Forces
- The weakest of the intermolecular forces
- the attraction between the positively
charged nucleus of an atom with the negatively charged electron cloud of a nearby atom - The more electrons a molecule has, the stronger it gets.
- This interaction creates an induced dipole.
London Dispersion / Van der Waals Forces
How bond strengths affect the Physical Properties of
Substances? (Just some info)
+ When the strength of forces decreases, so do the melting points, boiling points, and solubility in water. The vapor pressure and the solubility in nonpolar solvents increase.
+ When the strength of forces increases, it will result in higher melting or boiling points, which require breaking molecules apart. Higher intermolecular forces lead to a higher freezing point.
Bonding forces that influence Chemical Properties
Intramolecular Forces
Attracting forces that influence Physical Properties
Intermolecular Forces
Is anything that has
mass and takes up space
Matter
Will change the visible appearance,
without changing the composition of
the material
Can be irreversible or reversible
Physical Change
Change from a solid
to a liquid
Melting / Fusion
Change from liquid to
solid
Freezing / Solidification
Change from liquid to gas.
Evaporation
A change from solid
to gas without its
becoming liquid
Sublimation
When a substance in gas form a changes
states to become a solid
Deposition
Change from gas to
liquid
Condensation
A change where a new form of matter
is made
Chemical Change
SIGNS OF A CHEMICAL CHANGE
Gas production
Precipitate formation
Energy production
Change in temperature
Change in color
Change in chemical or physical property
Depends on the amount of matter in a
sample
- Volume, mass, size, weight, length
Extensive Property
Depends on the type of matter, not the amount present
- Boiling point, color, temp, luster, hardness
Intensive Property
A property that can be observed
and measured without changing the
materials composition
Physical Property