Chapter 9: Solutions Flashcards
Solvation is an (endothermic/exothermic?) process when the new interactions are stronger than the original ones. This is favored at low temperatures.
exothermic
Solvation is an (endothermic/exothermic?) process when the new interactions are weaker than the original ones. This is favored at high temperatures.
endothermic
what does solvation do?
breaks intermolecular interactions between solute molecules and between solvent molecules and forming new intermolecular interactions betweeen solute and solvent molecules together
At constant temperature and pressure, ________ always increases upon dissolution.
entropy
When the change in Gibbs free energy for the dissolution reaction is negative at a given temperature, the process will be ____________ and the solute is ____________. If positive, the process is ________________ and the solute is ____________.
spontaneous; soluble
nonspontaneous; insoluble
The most common type of solution is the ____________ solution, in which the solvent is water.
aqueous
Some solutions, such as acids, the formation of a complex called the ____________ ________ can occur. This occurs how?
hydronium ion (H3O+); H+ is donated from the molecule in solution to a water molecule
All salts containing ammonium (NH4+) and alkali metals are ____________.
soluble
All salts containing nitrate (NO3-) and acetate (CH3COO-) anions are ____________
soluble
Halides except fluorides are ________, except for those formed with which elements?
soluble; Ag+, Pb2+, and Hg22+
All salts of the sulfate ion (SO42+) are ____________, except for those formed with which elements?
soluble; Ca2+, Sr2+, Ba2+, and Pb2+
All metal oxides are ____________, except for those formed with which things?
insoluble;
1. alkali metals
2. ammonium
3. CaO, SrO, and BaO
THese all hydrolyze to form solutions of the corresponding metal hydroxides
All hydroxides are ____________, except for those formed with which things?
insoluble;
1. alkali metals
2. ammonium
3. Ca2+, Sr2+, and Ba2+
All carbonates (CO32-), phosphates (PO43-), sulfides (SO32-) are ____________ except for those formed with which things?
insoluble;
1. alkali metals
2. ammonium
ON MCAT, please know
Which 2 groups are always soluble?
- All salts of Group 1 metals
- All nitrate salts
________ and ________ ions are generally used as counterions to what is actually chemically important. Meaning, focus on the positive cation as the chemically reacting species.
sodium, nitrate
A ________ ion, or ____________ ____________, refers to a molecule in which a cation is bonded to at least one electron pair donor (which could include the water molecule)
complex; coordination compound
The electron pair donor molecules in coordination compounds are called ________.
ligands
e.g. The classic ligands that reversibly bind to hemoglobin, dioxygen, carbon dioxide, and protons, are bound covalently
Complexes are held together with ____________ ____________ bonds, in which an electron pair donor (a Lewis base) and an electron pair acceptor (a Lewis acid) form very stable Lewis acid-base adducts.
coordinate covalent
In some complexes, the central cation can be bonded to the same ligand in multiple places. This is called ____________, and it generally requires large organic ligands that can double back to form a second (or even third) bond with the central cation.
chelation
The normality (N) of a solution is equal to what?
The number of equivalents of interest per liter of solution
An equivalent is a measure of what? What is it equal to?
A measure of the reactive capacity of a molecule; it is equal to a mole of the species of interest
e.g. 1 mol of permanganate ion in acidic solution will readily accept 5 mol of e-, so a 1M solution would be 5 N
In solubility equations, equilibrium is defined as what?
The saturation point, where the solute concentration is at its maximum value for the given temp and pressure
What is molar solubility?
the concentration at saturation
____________ properties are physical properties of solutions that are dependent on the concentration of dissolved particles but not on the chemical identity of the dissolved particles.
colligative
Raoult’s law accounts for what?
vapor pressure depression caused by solutes in solution
On a molecular level, the presence of solute molecules can do what to evaporation? How about condensation?
block evaporation of solvent molecules; does not affect condensation
When a nonvolatile solute is dissolved into a solvent to create a solution, the boiling point of the solution will be (greater/less) than that of the pure solvent/
greater
what is the van’t Hoff factor?
the number of particles into which a compound dissolves into solution
The presence of solute particles interferes with the formation of lattice arrangement of solvent molecules associated with solid state. So, ____________ point is lowered with solute.
freezing
____________ ____________ refers to a “sucking” pressure generated by solutions in which water is drawn into solution. It is the amount of pressure that must be applied to counteract this attrattion of water molecules for the solution.
osmotic pressure