Entrance Exam Semmelweis with
Complete Solutions
Electron configuration for cations - ANSWER-Subtract 1 from exponent of highest n-
value orbital (ex. remove from 4s before 3d)
Ag+ = [Kr]5s^1 4d^9
Electron configuration for anions - ANSWER-Add 1 to closest orbital
Cl- = [Ne]3s^2 3p^6
Atomic orbitals - ANSWER-s, p, d, f
Primary vs secondary structures of proteins - ANSWER-Primary - AA chain (linked by
peptide bonds)
Secondary - stabilized by non-covalent bonds (alpha helices & beta sheets)
Most bonds in organic compounds are - ANSWER-covalent
Properties of water - ANSWER-1. polar
2. capable of adhesion and cohesion
3. high heat capacity (so it's hard to raise its temp)
4. great solvent
5. high heat of vaporization (allows humans to cool off via sweat)
6. water is less dense as a solid than a liquid
Intermolecular forces of water - ANSWER-hydrogen bonding
Solution components - ANSWER-1. solvent (product being dissolved)
2. solute (medium for dissolving solvent)
Molarity - ANSWER-the number of moles of solute per liter of solution
Solubility rules - ANSWER-SOLUBLE
1. alkali metals (group 1) & NH4+ cations
2. NO3- or CH3COO- anions
3. Cl, Br, I (except when bonded to Ag+, Pb2+ or Hg2+)
4. sulfate ions (except when with Ca2+, Sr2+, Ba2+, Pb2+)
,INSOLUBLE
1. Metal oxides (except CaO, SrO, BaO)
2. Hydroxides (except when with Ca2+, Sr2+, Ba2+)
3. Carbonates, phosphates, sulfides, and sulfites (unless bound to alkali metal or NH4+)
Solubility product - ANSWER-Ksp = [A]^a[B]^b
**only products because we don't include solids in the equilibrium expression
for NaCl
- Ksp = x^2
for PbCl2
- Ksp = 4x^3
for Cr(OH)3
- Ksp = 27x^4
Large Ksp means - ANSWER-strong electrolyte (more soluble)
Strong acids - ANSWER-So I brought no clean clothes
1. H2SO4
2. HI
3. HBr
4. HNO3
5. HCl
6. HClO4
7. HClO3
Strong bases - ANSWER-1. NaOH
2. LiOH
3. KOH
4. CsOH
5. RbOH
6. Ba(OH)2
7. Ca(OH)2
8. Sr(OH)2
Bases can certainly look pleasing (K), really something strong (Na)
Le Chatlier's principle: pressure - ANSWER-pressure applied (or volume reduced) -->
equilibrium proceeds in direction with fewer moles
pressure removed (or volume increased) --> equilibrium proceeds in direction with more
moles
, Le Chatlier's principle: temperature - ANSWER-increasing temperature
- toward products (if endothermic)
- toward reactants (if exothermic)
decreasing temperature
- toward products (if exothermic)
- toward reactants (if endothermic)
Le Chatlier's principle: concentration - ANSWER-increase concentration of reactants
- reaction shifts toward products
decrease concentration of reactants
- reaction shifts toward reactants
**the goal is to restore equilibrium
pH definition - ANSWER-pH = -log([H+])
Henderson-Hasselbalch equation - ANSWER-pH = pKa + log [Conj. Base]/[Acid]
**used to estimate pH of solution in buffer region (in which species and its conjugate are
in approximately equal quantities)
Redox reactions - ANSWER-reduction - gain of electrons
oxidation - loss of electrons
Oxidizing vs reducing agents - ANSWER-oxidizing agents cause oxidation (they are
reduced)
reducing agents cause reduction (they are oxidized)
Voltaic cell - ANSWER-AKA galvanic cell
Spontaneous, supply energy
- reaction with higher E is reduced (cathode)
- ex. Zn and Cu connected by salt bridge
Electrons flow from anode --> cathode
Energy flows from cathode --> anode
Reduction potential - ANSWER-Cathode minus anode
For voltaic cells, the higher value is the cathode
Complete Solutions
Electron configuration for cations - ANSWER-Subtract 1 from exponent of highest n-
value orbital (ex. remove from 4s before 3d)
Ag+ = [Kr]5s^1 4d^9
Electron configuration for anions - ANSWER-Add 1 to closest orbital
Cl- = [Ne]3s^2 3p^6
Atomic orbitals - ANSWER-s, p, d, f
Primary vs secondary structures of proteins - ANSWER-Primary - AA chain (linked by
peptide bonds)
Secondary - stabilized by non-covalent bonds (alpha helices & beta sheets)
Most bonds in organic compounds are - ANSWER-covalent
Properties of water - ANSWER-1. polar
2. capable of adhesion and cohesion
3. high heat capacity (so it's hard to raise its temp)
4. great solvent
5. high heat of vaporization (allows humans to cool off via sweat)
6. water is less dense as a solid than a liquid
Intermolecular forces of water - ANSWER-hydrogen bonding
Solution components - ANSWER-1. solvent (product being dissolved)
2. solute (medium for dissolving solvent)
Molarity - ANSWER-the number of moles of solute per liter of solution
Solubility rules - ANSWER-SOLUBLE
1. alkali metals (group 1) & NH4+ cations
2. NO3- or CH3COO- anions
3. Cl, Br, I (except when bonded to Ag+, Pb2+ or Hg2+)
4. sulfate ions (except when with Ca2+, Sr2+, Ba2+, Pb2+)
,INSOLUBLE
1. Metal oxides (except CaO, SrO, BaO)
2. Hydroxides (except when with Ca2+, Sr2+, Ba2+)
3. Carbonates, phosphates, sulfides, and sulfites (unless bound to alkali metal or NH4+)
Solubility product - ANSWER-Ksp = [A]^a[B]^b
**only products because we don't include solids in the equilibrium expression
for NaCl
- Ksp = x^2
for PbCl2
- Ksp = 4x^3
for Cr(OH)3
- Ksp = 27x^4
Large Ksp means - ANSWER-strong electrolyte (more soluble)
Strong acids - ANSWER-So I brought no clean clothes
1. H2SO4
2. HI
3. HBr
4. HNO3
5. HCl
6. HClO4
7. HClO3
Strong bases - ANSWER-1. NaOH
2. LiOH
3. KOH
4. CsOH
5. RbOH
6. Ba(OH)2
7. Ca(OH)2
8. Sr(OH)2
Bases can certainly look pleasing (K), really something strong (Na)
Le Chatlier's principle: pressure - ANSWER-pressure applied (or volume reduced) -->
equilibrium proceeds in direction with fewer moles
pressure removed (or volume increased) --> equilibrium proceeds in direction with more
moles
, Le Chatlier's principle: temperature - ANSWER-increasing temperature
- toward products (if endothermic)
- toward reactants (if exothermic)
decreasing temperature
- toward products (if exothermic)
- toward reactants (if endothermic)
Le Chatlier's principle: concentration - ANSWER-increase concentration of reactants
- reaction shifts toward products
decrease concentration of reactants
- reaction shifts toward reactants
**the goal is to restore equilibrium
pH definition - ANSWER-pH = -log([H+])
Henderson-Hasselbalch equation - ANSWER-pH = pKa + log [Conj. Base]/[Acid]
**used to estimate pH of solution in buffer region (in which species and its conjugate are
in approximately equal quantities)
Redox reactions - ANSWER-reduction - gain of electrons
oxidation - loss of electrons
Oxidizing vs reducing agents - ANSWER-oxidizing agents cause oxidation (they are
reduced)
reducing agents cause reduction (they are oxidized)
Voltaic cell - ANSWER-AKA galvanic cell
Spontaneous, supply energy
- reaction with higher E is reduced (cathode)
- ex. Zn and Cu connected by salt bridge
Electrons flow from anode --> cathode
Energy flows from cathode --> anode
Reduction potential - ANSWER-Cathode minus anode
For voltaic cells, the higher value is the cathode
