Review 1 Flashcards
3 Indicators and their Range
- Methyl Red = 4.4 - 6.2
- Bromothymol Blue = 6 - 7.6
- Phenolphthalein = 8.2 - 10
Two Methods for Alpha amino acid Synthesis
- Gabriel Synthesis
2. Strecker Synthesis
Gabriel Synthesis
N-pthalimidomalonic acid (2 COOEt (One for COOH and the other to activate COOH and N-bound to aromate for Amino Group) -> Alkylated to add R group (use base and R-X) -> Acid-hydrolysis (to add Nitro and carboxy on both siddes) -> Heat to form the alpha-amino acid and addition of H and removal of one of the COOH
Strecker Synthesis
- Aldehyde or Ketone acts as the backbone for amino acid
- :NH3 = Precursor for amino group
- KCN = Precursor for Carboxy group
Strecker Synthesis Process
Aldehyde or Ketone + :NH3 -> Water and Imine
Imine with Acid and KCN -> Alpha amino nitrile + acid -> amino acid
Transport Proteins
The higher the concentration of the ligand, the higher the binding affinity while the lower the concentration of the ligand, the lower the binding affinity
Purines
Adenine and Guanine
Pyrimidines
Cytosine and Thymine
Difference between Purines and Pyrimidines
Purines have a double ring structure and Pyrimidines hae a single ring structure
Why is DNA called an acid even with Nitrogenous bases
They have phosphate groups that are usually protonated but remain deprotonated in the solvent.
Saponification
Base-Catalyzed Ester hydrolysis of triglycerols that lead to polar and non-polar sides for soaps to function. This is the process by which fats are metabolized.
Types of Lipids
Hydrolyzable and Non-hydrolyzable lipids
4 examples of hydrolyzable Lipids
- Triglycerols - Saponification
- Phospholipids - Hydrolyzable because of phosphate
- Sphingolipids - Sphingosine + substituting OH for phosphate
- Waxes - Hydrolyzable because of the C=O
1 = Energy storage and 2 = Structural function
3 examples of non-hydrolyzable lipids
- Prostagladins - Inflammation signalling molecule
- Steroids - 6-6-6-4 rings with differing substituents for structural purposes
- Vitamins - Cofactors
a. A - Retinol (light sensitivity)
b. D - Bones (Rickets and Osteoporasis)
c. E - Antioxidant (protects neurological function)
d. K - Prothrombin (blood clot)
Effect of Common ion on Solubility
Common ione effect decreases solubility and shifts the equilibrium to the left as a result of Le Chatelier’s principles
Effect of pH on solubility
If the salt dissociating has a strong conjugate base, it will combine with the proton and form an acid and water. Note it does not work on all salts because the stronger the acid, the weaker the conjugate base. For example:
CaF2, F- will combine with H+ to form a weak acid but AgCl2 will not form an acid because it has a weak conjugate base and strong acid.
Effect on equilibrium of solubility from pH
The proton reacts with the specific ion and takes it out of solution, this will shift the equilibrium to the right to relieve the stress
Effect of dissolving NH3 and AgCl2
This will lead to the dissolution of AgCl2 into Ag 2+ and Cl-, the Ag 2+ will combine with NH3 to form a complex ion which is highly favorable. The overall effect is that more of AgCl2 will dissolve because the equilibrium shifts to the right
Acid/base NH3 and AgCl2 explanation
NH3 acts as a Lewis base (electron pair donor) and Ag2+ acts as a Lewis acid (electron pair acceptor)
CASHNGIA Explanation
C - Chlorates A - Acetates S - Sulfates H - Halides N - Nitrates G & I - Group I metals A - Ammonium
Electromagnetic Spectrum
Radio Waves Microwave Infrared Visible Ultraviolet (UV) rays X-rays Gamma rays
RMIVUXG
Rose and Malik Invited Vanessa and Umar to Xtra Glasses
Separation by Precipitation
The compound with the smallest value of molar solubility precipitates from solution first
Trick of Ion-exchange Chromatography
Exchanges one ion in solution for another which is initially bound to the column
TRICK: The column is filled with an ion exchange resin. The cation to be precipitated must have a lower molar solubility with the anion of the resin than the salt in the resin.
Ionic Rules on Solubility
- The greater the ionic forces (attraction), the less soluble
- The greater the charge, the less soluble
- The greater the size, the more soluble
Oxides and Solubility
Most Oxides and hydroxide salts are only slightly water soluble. KOH and NaOH are notable exceptions that are substantially soluble
Phase changes and Solubility
- Solubility of solids in liquids INCREASE with increasing temperature
- Solubility of gases in liquids DECREASE with increasing temperature
- Solubility of gases in liquids INCREASE with increasing pressure
Colligative Properties
- Depends on NUMBER of solutes NOT TYPE of solutes
- Boiling point elevation and Vapor Pressure depression
- Freezing point depression and Osmotic Pressure
Vapor Pressure
Pressure exerted by gaseous phase of a liquid that evaporated from the exposed surface of a liquid.
- Increased intermolecular forces, vapor pressure decreases
- Increased temperature, vapor pressure decreases
- Atmospheric pressure increases, vapor pressure stays the same
- Solute concentration increases, vapor pressure decreases
Osmotic Pressure
The pressure it would take to stop osmosis from occurring
Freezing Point Depression
- Freezing point DECREASES with soluble impurities added to the solution
- Presence of solute particles will interfere with efficient arrangement of the solvent molecules into solid lattice
Boiling Point Elevation
- Boiling point of a solution increases with the addition of impurities
- Attributed to both a decreased surface area from which the liquid can evaporate and an increase in the intermolecular forces binding the liquid solution.
Boiling Point
Pressure at which the vapor pressure of the solution is equal to the atmospheric pressure over the solution
Salt Bridge
- Helps equalize and neutralize salt bridge
2. Helps maintain balance
Terminal and Electrodes of Voltaic/Galvanic/Electrochemical Cell
Anode - Negative because electrons are generated from here (oxidation occurs here since electrons are generated)
Cathode - Positive because electrons come here and reduction because electrons cause reduction here
Factors Affecting the Cathode and Anode
- Ions
- Temperature
- Pressure
- Concentration
Free energy and Cell Potential Relationship
G = nFE
Define Faraday
Magnitude of charge carried by 1 mole of Electron
Standard Reduction Potentials
Down - Increasing Reducing agent and Up is increasing oxidizing agent Ag+ Cu2+ H+ Zn2+ Li+
Peculiar Property of Free energy and Standard Potential
Standard Potential is an intensive property (does not change)
Free energy is an extensive property (changes)
How can Activity series be explained
Use the standard reduction potentials
Relate Standard Cell Potential and Equilibrium Constant
-nFE = -RTlnK
From,
G = -nFE and G = -RTlnK (Remember all are in Standard G)
Essence of Nernst Equation
To calculate the standard cell potential when in non-standard conditions:
G = G' + RTlnQ -nFE = -nFE + RTlnQ
Standard Conditions
Standard Conditions:
- Temperature = 25 degrees
- Liquids and gases are pure
- Solutions = 1 M
- Energy of formation = 0
- Pressure = 1 atm
STP
Standard Temperature and Pressure:
- Temperature = 0 degrees
- Pressure = 1 atm or 1*10^5 Pa
- No of moles of gas = 1 mole
- Volume = 22.4 L
Effect of Q on E
As Q increases, E decreases
Terminal type and Electrode at a Electrolytic Cell
Cathode - Negative (reduction occurs here and electrons are coming from battery source
Anode - Positive (oxidation occurs here because it is the opposite)
Concentration Cell
Cell is the same electrodes (elements) but voltage generates as a result of tendency to become equally concentrated. Use the Nernst equation to find out what is the voltage since standard cell potential should be zero
Difference between Voltaic/Galvanic/Electrochemical cell and Electrolytic cell
The former occurs as a result of being spontaneous while the latter is a result of non-spontaneous reaction
Redox Reactions Balance
- Write each of the half reaction
- Balance the atoms other than O and H
- Balance the oxygen by adding H2O
- Balance the hydrogens by adding H+/OH- (Acids/Bases)
- Balance the charges by adding electrons
- Make the number of electrons equal, and add the half reaction.
