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Flashcards in Test 4 Deck (16):

Henderson-Hasselbalch Equation

pH = pKa + log([conjugate base]\[acid])

pKa = -log(Ka)


Strong Acids

Hydrochloric acid - HCl
Hydrobromic acid - HBr
Hydroiodic acid - HI
Nitric acid - HNO3
Perchloric acid - HClO4
Sulfuric acid - H2SO4
Chloric acid - HClO3


Strong Bases

Lithium hydroxide - LiOH
Sodium hydroxide - NaOH
Potassium hydroxide - KOH
Calcium hydroxide - Ca(OH)2
Strontium hydroxide - Sr(OH)2
Barium hydroxide - Ba(OH)2


Equation for Percent Ionization

(amount of acid ionized/initial amount of acid) * 100


Relationship between Q and Ksp Related to Precipitate Forming

If Q > Ksp, precipitate will form
If Q <= Ksp, no precipitate will form

Q involves calculating a solubility product with the initial concentrations of the system, then comparing the Q value to Ksp


Charges of columns in periodic table

Column 1 = +1
Column 2 = +2
Column 13 = +3
Column 12 = +2
Column 11 = +1
Column 18 = 0
Column 17 = -1
Column 16 = -2
Column 15 = -3


Group 1 Cations

Ag+, Hg2+, Pb2+
React with HCl to form precipitates


Group 2 Cations

Bi3+, Cd2+, Cu2+, Sn2+
React with H2S in an acidic solution to form Bi2S3, CdS, CuS, SnS


Group 3 Cations

Al3+, Co2+, Cr3+, Fe2+, Mn2+, Ni2+, Zn2+
React with H2S in a basic pH to form precipitate metal sulfide. Exception with Cr3+ that forms Cr(OH)3


Group 4 Cations

Ba2+, Ca2+, Sr2+
React with Na2CO3 to produce BaCO3, CaCO3 and SrCO3, precipitates, respectively


Group 5 Cations

K+, Na+, NH4+
K+ and Na+ must be a flame test where K+ is violet and Na+ is yellow. NH4+ can be detected by the addition of NaOH and smelling the obvious ammonia odor.


Factors that lead to increase in entropy

1.) A transition from a condensed phase to the vapor phase
2.) A reaction that produces more product molecules than reactant molecules in the same phase.


Change in free energy of a system equation

change in G = change in H - (T * change in S)

change in H = change in heat
T = temperature
change in S = change in entropy
change in G = change in Gibbs free energy


Relationship between change in G and spontaneity of the system

If change in G < 0, the reaction is spontaneous in the forward direction
If change in G > 0, the reaction is non-spontaneous, but spontaneous in the reverse direction
If change in G = 0, the system is at equilibrium


Heat transfer formula

Q = mc * change in T

Q = heat content in Joules
m = mass
c = specific heat, J/(g * degrees C)
change in T = temperature change in degrees C


Relationship between K (equilibrium constant) and change in G

If K > 1, change in G will be negative (products are favored over reactants at equilibrium - will shift to left)
If K = 1, change in G will = 0 (products and reactants are equally favored at equilibrium - no shift)
If K < 1, change in G will be positive (reactants are favored over products at equilibrium - shift to right)