Chemist talks to class of 5th graders
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Atoms, Molecules and Chemistry Dr. Chris Welch, Ph.D. Process Research Analysis & Preparative Separations Cranbury Elementary Cranbury, NJ April 2005
Transcript of Chemist talks to class of 5th graders
Atoms, Molecules and Chemistry
Dr. Chris Welch, Ph.D.Process Research
Analysis & Preparative Separations
Cranbury Elementary Cranbury, NJ
April 2005
Democritus(c. 460–c. 370 B.C.) matter is made of discrete indivisible particles, or atoms
Atoms
Dimitri Mendeleev (1834-1907)
Jacobus Henricus van't Hoff 1852 -1911
Friedrich August Kekulé1829- 1896
Molecules
MoleculesCOOH
O CH3
O
aspirin
C
OCH3
OH
O HCOOH
O CH3
O
aspirinvanillin
N
N N
N
O
H3C
O
CH3
CH3
caffeine
HN
N N
N
O
O
CH3
CH3
theobromine
CH3
CH3
HO
H3C CH3
CH3
H
H H
H
cholesterol
CH3
CH3
CH3CH3
CH3CH3
CH3
CH3
H3C
H3C
beta carotene
CH3
O
HC
CH3 CH3
all-trans Retinal
H3C CH3
(vitamin A)
CSP
analyte enantiomers k’1 = t1 - to
to
k’2 = t2 - toto
α = k’2
k’1
More stable adsorbate
Less stable adsorbate
b d p q
NHO
N
O
PhNO
N
N
MeO
O N
H
O
OH
1
H
CF3
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
0 2 4 6 8 10 12 14 16
Tim e (m in)
UV
@ 3
20 n
m
A B F1F2
F3
F4
‘dimer’
5.6 kg of 2 obtained from 19 runs
290 g/injection< 5 hours1.9 kkd 400L/kg
O
SN
O
O
HH
O
O
(S,S) Whelk-O CSP
(S) L-828,198
amide hydrogen
methine hydrogen
carbonyl oxygen
hydrogen bond
π- π interaction
methine hydrogen
1:1 complex(3R, 4S) - 2
(S) - 1
1:1 complex
Team Lead: Pat Beauchamp, Jet Propulsion LaboratoryUniversity Lead: Jonathan I. Lunine, Lunar and Planetary Laboratory,
The University of ArizonaTeam
Jack Beauchamp, Beckman Institute and Dept. of Chemistry, Caltech Dennis Dougherty, Dept. of Chemistry, CaltechGene MacDonald, Jet Propulsion LaboratoryMark Smith, Department of Chemistry, U of AChris Welch, Merck and Co.
ChiMERAChiMERA Project (Chiral Measurements for Project (Chiral Measurements for Extraterrestrial Robotic Analyses)Extraterrestrial Robotic Analyses)
A U of ArizonaA U of Arizona--CaltechCaltech--JPLJPL--MRL PartnershipMRL Partnership
Cassini Orbiter releasing Huygens probe
Huygens Probe
Huygens GC/MS17 kg
Aerobot approach Aerover approach
Titan Organics Explorer follow-up to Cassini-Huygens?
Conclusion
Atoms are cool.Molecules are fun.
There are many new things waiting to be discovered in….
CHEMISTRY, the central science.
