analytical 1
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Define Selectivity.
Selectivity is the ability to distinguish diferent components of a sample.

Define Sensitivity.
Sensitivity is the ability of an instrument to descriminate between small difference in [analyte].

What is Analytical Sensitivity?
Slope/Standard deviation, defined from concentration.

What are the 2 factors of sensitivity?
 1) precision
 2) Slope of Calibration Curve

Define Linearity.
Linearity is in reference to the plots of a calibration curve to be one dimensional in respect to eachother with a high r^2 value close to 1.

Define Range.
Range is the area of variation in the upper and lower limits of the detection limit.

What are the two kinds of ranges concerning the sensitivity of an instrument.
When discussing the sensitvity of an instrument the two things to be considered are:
Limit of Detection:
Limit of quantification:

Define Detection Limit i.e. Limit of dection.
The limit of dection is the minimum amount of analyte that can be detected by a method @ a known confidence level.

Define the limit of quantification.
The limit of quantification is the smallest amount that the researcher can measure with reasonable accuracy with that instrument.

What is the minimal extingguishable signal of an instrument?
The minimal extinguishable signal of an instrament is determined by
This is also known as calculating the figures of Marrit (FOM)

What is the Nernst Equation?

Define polarization.
Polarization is the deviation of electric potential from the predicted value of the nernst equation.
 Attributed to 2 things:
 1. concentration polarization
 2. kinetic polarization

What is Kinetic Energy?
The over potential required to overcome the activation energy

grams of a solid reacted on working electrode?
moles reacted =

What is the basic set up for a 3electrode system?
 Working electrode: where rxn of interest occurs
 Auxillary electrode: Completes circuit w/o adding additional
 elecrons
 Reference electrode: measures potential directly at the working electrode

Discribe strengths and weaknesses of the voltammerty technique:
linearsweep
 Weaknesses:
 charging current
 can only distinguish peaks of 0.02 V apart
 sensitivity of 10^4

Discribe strengths and weaknesses of the voltammerty technique:
Differential pulse polargraphy
 Strengths:
 Peaks are more easily distinguished
 enables the ability to distinguish peaks from 0.04 V from eachother
 Sensivity of 10^7 to 10^9
Weaknesses:

Discribe strengths and weaknesses of the voltammerty technique:
square wave voltammetry
Strengths:
 1)most effective excitation signal
 2) Very fast 10ms to yield data
 3) Same sensitivity as DPP (10^7 to 10^9)
 4) high [ ] of analyte at surface

Discribe strengths and weaknesses of the voltammerty technique:
Cyclic Voltammetry
strengths:
 1) Mostly qualitative, can be quantitative
 2) studies redox reactions and intermediate
Weaknesses:
1) not as sensitivity as pulse methods

Discribe strengths and weaknesses of the voltammerty technique:
Stripping analysis
Strengths:
 1) great for small amounts of sample
 2) Sensitivity of ^6 to 10^9

define frequency
the number of oscillations of the electric field vector per unit time
units: 1/p

define velocity and units
The velocity of a wave is the length the wave travels over time.
This value is known as the speed of light, 3.0x10^8 m/s or 3.0x10^10 cm/s

Define wavelength
The linear distance between successive maxima or minima of a waves
Units: cm s^1

define wave number
Wave number is defined as the number of waves per centimeter and is equal to
Units: cm^1

what is plank's constant and the equation to calculate energy in joules
Plank's Constant 6.63x10^34

define Emission spectroscopy
Emission spectroscopy is the excitation by heat or a chemical rxn (chemiluminescence) to monitor wavelengths of light that is emitted.

Define: Photoluminescence spectroscopy
excitation by electromagnetic radiation, 2 types
 1) fluorescence
 2) phosphorescence

define fluorescence
emission occurring fro s1 to s0, 10^4 sec to 10^8

define phosphorescence
emission occurring from T1 to S0 between states of different mutiplicity

define absorbance
pass light through a sample and measure absorbance as a funcition of wavelength

What are Beers law's limitations?
Beers Law's limitations are:
 1) only work ok dilute samples
 2) If particles are close, they will affect eatchothers charge distrucbution.
 3) if close, it will aslo affect the spectrum and linearity
 4)can get complexs and ppt that affect spectrum (chemical deviations)
 5) association and dissociation rxns with solvents or other molecules in matrix
 6) Instrument deviation, quality of monochrometer