MAAFI

Question 1

What equation to use for Calibration Graphs?

Answer 1

Beer-Lambert (y=m x + c)

Question 2

Absorbance Calibration graph Equation?

Answer 2

A=elc

Question 3

What does A=elc?

Answer 3

A= Absorbance
e= Extinction Coefficient
l= Optical Length
c= Speed of Light

Question 4

Absorbance:

In A=elc, what part of Beer-Lambert eqtn. do you get if you multiply E and L?

Answer 4

A=elc

e*l= Extinction Coefficient @ a KNOWN wavelength = M
Y= M X + C

Question 5

Define:

QUANTITY.

Answer 5

How much of a substance there is?

Question 6

Define:

QUALITY.

Answer 6

What is the subtstance?

Question 7

Define:

Accuracy

Answer 7

Closeness to REAL value

Question 8

Define:

Precision

Answer 8

Closeness of a SERIES of values

Question 9

Define:

Accuracy & Precision

Answer 9

Closeness of a SERIES of values to the REAL/TRUE value

Question 10

SPECTROSCOPY:

What is light?

Answer 10

Light is a propagating electromagnetic wave.

Question 11

What is the equation for finding out Wavelengths, Frequencies, Energy and Wavenumbers?

Answer 11

E= hc/LAMBDA = hc*V

Question 12

Define E, h, c, LAMBDA and V.

Answer 12

E - Energy
h - Planck's Constant
c - Speed of Light
f - Frequency
LAMBDA - Wavelength
V - Wabenumber

Question 13

Units for:
E
h
c
f
LAMBDA
V

Answer 13

E= Joules
h= 6.62 x10^10-34J/s
c= 3x10^8 m/s
f= Hz (/s)
LAMBDA= nm
V= Cm-1

Question 14

3 Steps to finding out Electromagnetic Properties using Spectroscopy Equation? (Before rearranging)

You’ll need to IDENTIFY:

Answer 14

1) What you HAVE.
2) What you NEED.
3) Which part of the EQUATION you NEED.

Question 15

SPECTROSCOPY:

Sigma electrons make:

Answer 15

Sigma Bonds!

Question 16

SPECTROSCOPY:

π electons make

Answer 16

π Bonds!

Question 17

Which type of bond requires more energy to break into Anti-bonding?

Answer 17

SIGMA BONDS

Question 18

Photo-degradation is caused by which type of anti-bonding?

Answer 18

SIGMA –> SIGMA* Antibonding

Question 19

Bond breaking (Sigma* bonds) would cause the formation of a new product (degradation product).

What would this new molecule cause?

Answer 19

A new shift in the absorbance spectrum as each molecule will have its own absorbance.

Question 20

SPECTROSCOPY:

Wavelength boundaries for UV

Answer 20

200-370 nm

Question 21

SPECTROSCOPY:

Wavelength boundaries for Vis

Answer 21

380-700 nm

Question 22

Pi bond wavelength peak guides…

Answer 22

~ 200-800nm

Question 23

Sigma bond wavelength peak guides…

Answer 23

~ <210mm

NOTE: How this is significantly smaller THEREFORE smaller LAMBDA = higher E

Question 24

Wavelength for anything coloured..

Answer 24

ABOVE 370 nm

Question 25

Types of CHROMICS for CONJUGATION

Answer 25

BATHOCHROMIC HYPERCHROMIC

Question 26

Define BATHOCHROMIC

Answer 26

BATHOCHROMIC: In conjugation, denoted by an INCREASE in WAVELENGTH (LAMBDA)

Question 27

Define: HYPERCHROMIC

Answer 27

HYPERCHROMIC: In conjugation, denoted by and INCREASE in Extinction Coefficient (e)

Question 28

What is meant by CONJUGATION?

Answer 28

The term used to describe the structure of a hydrocarbon with alternating CARBON=CARBON-CARBON=CARBON bonds. The movement of π e-.

Question 29

How are ELECTRONIC TRANSITIONS induced?

Answer 29

By Photon Absorption

Question 30

SPECTROSCOPY: Requirements for UV Spec.

Answer 30

Quartz cell/curvette. NON-COLOURED/VISIBLE

Question 31

SPECTROSCOPY: Bonding/Anti-bonding gap...

Answer 31

The gap is DIRECTLY PROPORTIONAL to the Energy CHANGE

Question 32

SPECTROSCOPY: MAAFIs Tips: What are the 5 steps for the Procedure of CONVERSIONS?

Answer 32

1) IDENTIFY Quantity (and UNITS that you have and REQUIRE) 2) Use and CHOOSE Energy equation component for the units you require. 3) Rearrange & CANCEL out 4) CHECK units & make sure they correspond 5) Adjust & Converge units to SI or whatever question requires! DOUBLE CHECK Ans. units

Question 33

SPECTROSCOPY: STERN-VOLMER relates to?

Answer 33

QUENCHING

Question 34

Electronic Transition: Electrons can be what types?

Answer 34

SIGMA PI N

Question 35

Electronic Transition: | sigma, pi and n electrons sit on...

Answer 35

Molecular orbitals in the GROUND STATE (GS)

Question 36

Electronic Transition: Molecules can only go from...

Answer 36

Bonding or Anti-bonding states.

Question 37

Electronic Transition: (graphs) First Peak=

Answer 37

High Energy

Question 38

Electronic Transition: (graphs) Last Peak=

Answer 38

Low Energy Transmission

Question 39

Electronic Transition: (graphs) High Energy Transmission indicates a....

Answer 39

SIGMA ANTI-bonding... If the LAMBDA/Wavelength is SMALL then it would obvz. require more energy!

Question 40

Electronic Transition: (graphs) There is a peak in the visible spectrum. What does this indicate?

Answer 40

A π --> π*

Question 41

STOKES' SHIFT: The last peak indicates...

Answer 41

The LOWEST possible energy.

Question 42

STOKES' SHIFT: | Definition

Answer 42

The measurement between the two closest MAXIMA (highest peaks) between EMISSION AND ABSORPTION

Question 43

STOKE SHIFT: | Is good for...

Answer 43

Quantitative Analysis For finding out what HAPPENED to that molecule under those experimental conditions

Question 44

STOKE SHIFT: | S1 =

Answer 44

The lowest possible energy

Question 45

JABLONSKI: | Definition

Answer 45

Exploring the possible fates of an excited MOLECULE.

Question 46

JABLONSKI: The transition between Ground State to Excited State requires....

Answer 46

Energy/Light

Question 47

JABLONSKI: ``` INTERNAL CONVERSION (IC) Can occur between... ```

Answer 47

Ground and Excited SINGLET STATES

Question 48

JABLONSKI: | Once a molecule has relaxed to S1 state, what happens?

Answer 48

The higher energy is dissipated down. VIA - Emission of Light/Heat

Question 49

JABLONSKI: One molecule...

Answer 49

ONE MOLECULE ONE TRANSITION ONE ELECTRON

Question 50

JABLONSKI: | INTERSYSTEM CROSSING

Answer 50

ISC - S1 to T1 OR Vice-Versa

Question 51

ISC to Ground State results in..

Answer 51

LIGHT (Photoreactions)

Question 52

JABLONSKI: Define - | INTERSYSTEM CROSSING

Answer 52

Losing an e- to go from one energy state to a lower energy state. S1 - T2 or T1 - S0

Question 53

Do all molecules Fluoresce/Phosphorescence all the way down to GS/S0?

Answer 53

NO. All items in JABSLONSKI can dissipate via Vibration energy, Light Emission or Heat Emission.