CHEM/PHYS Flashcards
What are characteristics associated with dehydration reactions ?
Dehydration reactions:
- tertiary alcohol readily dehydrate
- form carbocation intermediate
- involves loss of water molecule
- mixture of cis and trans products
- NOT Stereospecific
What functional group represents a peptide bond?
AMIDE group
What makes nucleophilic substitution slower ?
When there is crowding of groups at a carbon (steric hindrance)
In Gas chromatography, what is the first peak to emerge?
The Least Polar, Most Volatile compound will be first to emerge
what kind of compounds are very volatile ?
compounds that have LONDON dispersion forces
(meanwhile hydrogen bonds are least volatile)
What are the differences between SN1 and SN2 ?
To be continued (find out)
Compare and contrast the signs of diverging vs converging lens ?
Diverging lens (negative sign)
converging lens (positive sign)
What is thin lens formula ? What are units ?
Thin lens formula : 1/focal length = 1/ object + 1/ image
Units : D (diopter) 1D = 1m ^-1
How does an enzyme work ?
An enzyme stabilizes the transition state, thus lowering the activation energy of a reaction.
What can decrease the percent ionization (dissociation of ions) of a compound ?
Adding a STRONG ACID that will increase the amount of H+ in solution and ( thus decrease the percentage ionization)
What is ohm’s Law?
V= IR
What is index of refraction formula?
The index of refraction : speed of light in vacuum / the speed of light in the medium.
What is the intensity of electromagnetic radiation ?
intensity of electromagnetic radiation is defined as energy emitted per unit time.
What is the energy of electromagnetic radiation proportional to?
proportional to number of photons
What is THz when it comes to frequency ?
THz = 1 trillion hertz (1012 Hz) when measuring frequency
what formula can be used to calculate fraction of radioactive decay ?
1/2 ^n
n= number of half lives
first value after equation (how much if isotope is left)
What is the formula for volume flow rate ?
Q = Vt
Q= volume flow rate
V= volume
t= time
What is the formula for Power ? What is the unit for power ?
P = work/ time
unit : Watts (W)
What is the unit for Work ?
unit: Joules (J)
What kind of bonding enhances rigidity of a compound ?
INTERMOLECULAR bonding enhances rigidity of a compound
What is the difference between intramolecular and intermolecular bonding ?
Intermolecular : are the attractions between molecules
Intramolecular : forces WITHIN molecule that hold it together
What are the different intramolecular forces ?
intramolecular forces: covalent, ionic and metallic bonding
What are the different intermolecular forces ?
Intermolecular forces: ion-ion interactions, dipole-dipole, hydrogen bonding and london dispersion force
What kind of force is disulfide bridge?
intermolecular covalent bond