PHYSICOCHEMICAL PROPERTIES Flashcards
A property that does not affect the chemical identity of a compound.
Physical Property
Can be observed and measured without changing a compound’s composition of matter.
Physical Property
Any substance that has mass and can occupy space.
Physical Property
2 Types of Physical Property
Intensive / Intrinsic
Extensive / Extrinsic
Independent of system size or material content.
Intensive / Intrinsic Property
Example of this property are boiling points, melting points, temperature, density, etc.
Intensive / Intrinsic Property
Boiling point of water.
100°C
Dependent of system size or material content.
Extensive / Extrinsic Property
Example of this property are weight, height, mass, length, etc.
Extensive / Extrinsic Property
Within the molecule.
Intramolecular
Between the molecules.
Intermolecular
The physical properties of molecules are in part dependent on ?
the types of IMF present
Boiling points (BP) are dependent on ?
the mass of the molecule
Solubility, the ability to dissolve into a solvent, is dependent on ?
Intermolecular Forces (IMFs)
The strength of the interaction between molecules is also dependent on ?
the overall shape of the molecule
3 Types of Intermolecular forces, by decreasing strength they are:
- Hydrogen bonding
- Dipole-dipole
- London Dispersion
What is the strongest type of Intermolecular forces?
Hydrogen bonding
A complex interaction that includes dipole-dipole, as well as orbital interactions and the transfer of electron density between molecules.
Hydrogen bonding
These are the strongest of the IMFs.
Hydrogen Bonding
Hydrogen bonding ranges from what kJ/mol?
5 - 25 kJ/mol
Dipole means?
Polar
Induced Dipole means?
Non-polar
Interaction between polar and polar?
Dipole-dipole
Interaction between polar and non-polar?
Dipole and Induced Dipole
Interaction between non-polar and non-polar?
Induced Dipole and Induced Dipole
Hydrogen bonding occur primarily between?
OH (Oxygen)
NH (Nitrogen)
FH (Fluorine)
In Hydrogen Bonding, the more ______ the atom the stronger the interaction.
Electronegative
In hydrogen bonding, the atom H is attached to usually has a ____ ____ of e-
lone pair
Forces arise from the attraction of OPPOSITELY charged atoms (other than H) In molecules.
Dipole-Dipole
This molecules may have a permanent dipole moment.
(Hindi madaling mag displace)
Dipole-Dipole
Generally in organic molecules they result from the presence of C-X (carbon bonded to an atom) where X is more electronegative to that of C.
Dipole-Dipole
Dipole-Dipole ranges from what kJ/mol?
5 - 10 kJ/mol
Permanent Dipole - Permanent Dipole (between 2 polar molecules) is also known as?
Keesom Force
Permanent Dipole - Induced Dipole is also known as?
Debye Force
Induced Dipole - Induced Dipole is also known as?
London dispersion force
Forces arise from the movement of electrons within a molecule.
London Dispersion
In london dispersion, the natural motion can produce an uneven distribution of the electrons (polarization of the distribution) resulting in a __________ in the molecule. This will induce the movement of electrons in adjacent molecules producing a dipole moment in them.
temporary dipole movement
In london dispersion, these “induced” dipole moments are very brief as they ________ when the electrons move to new locations within the molecule.
disappear
London Dispersion ranges from what kJ/mol?
2 - 5 kJ/mol
Other name of London Dispersion?
Induced Dipole - Induced Dipole
The strength of the IMFs depend on the ____________ between the molecules, especially for dispersion forces. Hence the shape of the molecule can affect the surface area of contact, long thin molecules have more surface in contact than spherical molecules.
amount of contact
The strength of the IMFs depend on the amount of contact between the molecules, especially for dispersion forces. Hence the ______ of the molecule can affect the surface area of contact, long thin molecules have more surface in contact than spherical molecules.
shape
Long thin molecules have more surface in contact than spherical molecules.
(True or False)
True
Molecules having a polar functional group have a higher________ than others with a non polar functional group of similar molecular masses.
boiling point
Factors affecting the physical properties of organic compounds
- Structure of Functional Group
- Molecules having a polar functional group have a higher boiling point than others with non-polar functional group of similar molecular masses
Molecules with _____ (longer) molecular masses have higher melting point, boiling point and density.
higher
formula of density
m
d × v
Molecules with BRANCHED chains have _____ boiling point and density that it’s straight chain isomer.
lower
__________ isomers have greater surface area in contact with each other. Greater attractive force among the molecules.
Straight-chain
Larger molecules have _____ boiling and melting points.
Higher
Mass is constant. Weight measures gravitational force (N).
Forces that hold atoms together within a molecule (inside the molecule).
Intramolecular Forces
4 types of Intramolecular Forces
- Ionic
- Polar covalent
- Non-polar covalent
- Metallic bond
Strongest INTRAmolecular force
Metallic bond
Weakest INTRAmolecular force
Non-polar covalent
London Dispersion is under?
van der Waals force
affected by the pull of gravity
weight