Intermolecular Forces (10.1) Flashcards
- Describe the types of intermolecular forces possible between atoms or molecules in condensed phases. (dispersion forces, dipole-dipole attractions, and hydrogen bonding). - Identify the type of intermolecular forces experienced by specific molecules based on their structures. - Explain the relation between the intermolecular forces present within a substance and the temperatures associated with changes in its physical state.
What are particle activities of a solid?
Particles are in tightly packed together in an arranged pattern but vibrate extremely fast.
What are particle activities of liquid?
Particles move past each other but remain essentially in a constant contact with each other.
What are particle activities of gas?
All the particles move independently except when they collide.
What are intermolecular forces?
Various types of forces that exist that causes the attractions of molecules not forces between atoms, that is the intramolecular force. The intermolecular forces is existent of multiple forces (Van der Waals Forces) due to electrostatic phenomena.
What are intramolecular forces?
The force that holds atoms together through covalent, ionic, metallic, and dative bonding.
Liquifying gases possible?
Yes it is possible if enough pressure is applied to the gas and it will be condensed enough to form a liquid.
What about if liquid becoming a solid?
Yes it is also possible, if temperature becomes low enough OR the pressure becomes high, the molecules of the liquid no longer have enough kinetic energy to over come the intermolecular forces between them. A solid will form.
Define dispersion forces
Weak attractions that occur between molecules, caused by instantaneous dipole.
- Weakest type of force but are important in keeping molecules together in gases and nonpolar substances.
What is Van der Waals forces?
Types of intermolecular forces that acts between molecules or between different parts of large molecules. They are generally weaker than hydrogen bonds or ionic bonds.
Forces:
- London Dispersion Forces
- Dipole-Dipole Forces
- Dipole-Induced Dipole Forces
They are present in all molecules and contribute to properties like boiling points, melting points, and solubility.
Define instantaneous dipole
Small, temporary shifts in where electrons are within an atom or molecule. These shifts create a momentary charges that make nearby molecules attract each other.
What is a dipole moment/dipole?
Separation of charge (causes partial charges) due to unequal sharing of electrons (polar).
Define induced dipole
A temporary dipole created in a nonpolar molecule from the presence of a nearby charge or dipole.
What happens to atoms from the periodic table as you go from top to bottom of the table?
The atomic radius gets bigger (bigger atom), so the attraction force becomes greater. The bigger the atom the stronger the dispersion force. Compared to smaller atoms.
What about physical properties of an atom as the atomic radius becomes bigger? (melting point, boiling point, etc.)
Those physical properties also increases.
Define polarizability
- How electrostatically charged a molecule is, if a molecule has a very distorted cloud of electrons (meaning electrons are more attracted to bigger atom), it means it is very polarizable.
- If a cloud is difficult to distort (electron cloud is in a neutral position or barely attracted to an atom in a molecule), means it’s not very polarizable.
