Chapter 0g: Solutions Flashcards
- homogeneous mixtures of two or more substances
- form when there is sufficient attraction between the solute and solvent molecules
solutions
two components of solutions
- solvent
- solute
present in larger amount
solvent
present in smaller amount
solute
Solutes and solvents may be… ?
- liquid
- gas
- solid
solutes are mixed with solvents so that they have the same __ __
physical state
solutes in a solution cannot be separated by __, but can be separated by __
- filtration
- evaporation
- one of the most common solvents in nature
- polar molecule due to polar O-H bonds
- molecules form hydrogen bonds
water
what type of molecule is water
polar molecule (O-H bonds)
How are solutions formed
solute-solvent interactions are large enough to overcome solute-solute interactions and solvent-solvent interactions
what dissolves what
like dissolves like
(polar - polar)
(nonpolar - nonpolar)
ex. of nonpolar molecules
- iodine
- oil
- grease
play an important role in maintaining proper function of cells and organs
electrolytes
Types of electrolytes
- strong electrolytes
- weak electrolytes
- nonelectrolytes
- dissociate 100% in water
- produce positive and negative ions
- form solutions that conduct an electric current strong enough to light a bulb
strong electrolytes
- dissociates only slightly in water
- forms a solution with a few ions and mostly undissociated molecules
weak electrolytes
- dissolve as molecules in water
- do not produce ions in water
- do not conduct an electric current
nonelectrolytes
Ex. of strong electrolyte formula
NaCl(s) –> Na+(aq) + Cl-(aq)
Ex. of weak electrolyte formula
HF(aq) <–> H+(aq) + F-(aq)
Ex. of nonelectrolyte formula
C12H22O11(s) –> C12H22O11(aq)
Examples of strong electrolytes
- ionic compounds
- acids such as HCl, HBr, HI, HNO3, HClO4, H2SO4
Examples of weak electrolytes
- HF
- H2O
- NH3
- HC2H3O2 (acetic acid)
Examples of nonelectrolytes
carbon compounds
- methanol (CH3OH)
- ethanol (C2H5OH)
- sucrose (C12H22O11)
- urea (CH4N2O)
amount of an electrolyte or an ion that provides 1 mole of electrical charge
equivalent (Eq)
In solution, the charge of positive and negative ions are always __
balanced
electrolytes in intravenous fluids are expressed in __
mEq/L
maximum amount of solute that dissolves in a specific amount of solvent
solubility
how is solubility expressed
g of solute / 100 g water
Two types of solution
- unsaturated solution
- saturated solution
- contain less than the maximum amount of solute
- can dissolve more solute
unsaturated solutions
- contain the maximum amount of solute that can dissolve
- have undissolved solute at the bottom of the container
- contain solute that dissolves as well as solute that recrystallizes in an equilibrium process
saturated solutions
saturated solution formula
solute + solvent –> (solute dissolves) (solute recrystallizes) <– saturated solution
where does solubility depend
temperature
solubility of solids:
temperature increases
more soluble
solubility of gases:
temperature increases
less soluble
- states that the solubility of a gas in a liquid is directly related to the pressure of that gas above the liquid
- at higher pressures, more gas molecules dissolve in the liquid
Henry’s law
when the pressure of a gas above a solution decreases, what happens to the solubility of that gas in the solution
also decreases
How are ionic compounds soluble in water
if they contain soluble cation or anion
Soluble in Water:
Positive ions
- Li+
- Na+
- K+
- Rb+
- Cs+
- NH4+
Soluble in Water:
Negative ions
- NO3 -
- C2H3O2 -
- Cl -
- Br -
- I -
- SO4 2-
Cl-, Br-, I- are insoluble when combined with…?
- Ag+
- Pb 2+
- Hg2 2+
SO4 2- is insoluble when combined with…?
- Ba 2+
- Pb 2+
- Ca 2+
- Sr 2+
- Hg2 2+
Ionic compounds that do not contai at least one of the soluble ions are usually __
insoluble
used to enhance x-rays
BaSO4
mass percent (m/m)
g/g
volume percent (v/v)
mL/mL
mass/volume percent (m/v)
g/mL
When writing a net ionic equation, what is removed
spectator ions
ions which do not participate in chemical reactions and present the same on both sides of the reactions
spectator ions
a solvent, usually water, is added to a solution, which increases its volume and decreases the concentration of the solution
dilution
what is added in a dilution
water
what is the same in the initial and diluted solution
moles of solute
equation that relate concentration and volumes
C1V1 = C2V2
concentration, C, may be __ or __
- percent concentration
- molarity
Freezing point depression of water
1.86°C kg/mol
Boiling point elevation of water
0.515°C kg/mol
