Chem exam 1 Flashcards
not to fail
Saturated Solution
Contains the maximum amount of solute that will disolve in a given solution
Unsaturated Solution
Contains less solute than the solvent has capacity to disolve
Supersaturated
Contains more disolved solute than solvent has capacity to disolve
Solubility
The ability of a solute to disolve in a solvent
expressed as:
S = Mass of Solute (g) / Volume of Solution (L)
Heat of solution
gas becomes less soluble as temp increases.
Solid/Liquid solutions increase solubility as temp increases.
Pressure of a solution
does not affect solid/liquid solubility.
higher pressure increases solubility in gaseous solutions.
Ion-dipole
The charge of an ion is attracted to the positive side of a polar molecule
Dipole induced dipole
The partial charge on a polar molecule induces a temporary partial charge on a neighboring nonpolar molecule or atom.
Ion induced dipole
The charge of an ion induces a temporary partial charge on a neighboring nonpolar molecule or atom
molality (m)
mols of solute / mass of solvent (kg)
colligative property
properties that depend on the number of solute particles in a solution but do not depend on the nature.
* vapor pressure-lowering
* boiling point elevation
* freezing point deprevation
* osmotic pressure
IMFs
- Hydrogen bonding- This is the strongest type of intermolecular force and occurs in molecules where hydrogen is directly bonded to highly electronegative atoms like O, N, or F.
- Dipole-Dipole Interactions: These occur between the positive end of one polar molecule and the negative end of another polar molecule.
- Ion-Dipole Interactions: These occur between ions and polar molecules.
- Dipole-Induced Dipole Interactions (London Dispersion Forces): This is a type of van der Waals force where a polar molecule induces a temporary dipole in a neighboring nonpolar molecule, leading to an attractive force. This force is generally stronger in larger, more polarizable molecules.
- Ion-Induced Dipole Interactions: These occur between an ion and a nonpolar molecule. The ion induces a temporary dipole in the nonpolar molecule, leading to an attractive force.
Raoults Law
Difference in vapor pressure of pure solvent and corresponding solution
𝑃𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 = (𝜒𝑠𝑜𝑙𝑣𝑒𝑛𝑡)(𝑃𝑠𝑜𝑙𝑣𝑒𝑛𝑡)
boiling point elevation
ΔT b=i⋅Kb ⋅m
freezing point deprevation
ΔT f=i⋅Kf ⋅m
Osmosis
Osmosis is the movement of solvent molecules (usually water) across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration. The key factor in osmosis is the concentration of solutes, not the type of solute molecules.
Osmosis equation
π=i⋅M⋅R⋅T
Where:
π is the osmotic pressure,
i is the van’t Hoff factor (the number of particles into which the solute dissociates in the solution),
M is the molarity of the solution,
R is the ideal gas constant (approximately 0.0821 L·atm/(mol·K)),
T is the absolute temperature in Kelvin.
Van’t Hoff factor
The van’t Hoff factor (i) represents the number of ions that a molecule dissociates into when it dissolves in a solution.
Mass
Volume x Density
Colloid
a dispersion of particles of one substance throughout another substance
1 nanometer (nm) to 1 micrometer (μm).
Like disolves like
two substances of similar IMF and magnitude are more likely to be soluble with one another.
Hydrophillic
substances that “love” water
* Hydrophilic molecules are typically polar or ionic, meaning they have regions with partial positive and negative charges.
* They readily dissolve or interact with water molecules.
* Examples of hydrophilic substances include salts, sugars, and many biomolecules like proteins and nucleic acids.
Hydrophobic
substances that “fear” water and repel it.
* Hydrophobic molecules are often nonpolar and lack regions with significant positive or negative charges.
* They do not readily dissolve in water and may aggregate to minimize contact with water.
* Examples of hydrophobic substances include fats, oils, and certain types of molecules in cell membranes.