CHAM lab
PH meter - answer thin walled bulb of glass containing 0.1M HCL in contact with a
metal wire electrode.
in solution, potential is et up across thin glass wall
compares signal to signal in standard buffer solution
buffer effectiveness depends on – answer pH, concentration, volume and identity
buffer capability at different pH ranges - answer phosphate buffer
what colour is ONP - answer yellow
at 420 nm
Jablonski Diagram - answer An energy diagram that illustrates the electronic states of a
molecule and the transitions between them;
the states are arranged vertically by increasing energy and grouped horizontally by spin
multiplicity.
within any energy level (S) there are - answer additional different energy levels arising
from different vibrational states (V1,V2)
how long does absorption take
how long is molecules excited for - answer10^ -15 seconds
10^-12 seconds, excited e- returns to one of the vibrational rotational levels associated
with the ground state
=coupled with loss of heat
light source used depends on - answerwavelength instrument can operate at
consistency of light source intensity
wavelength output
durability
cost
monochromator - answerseparate the light emitted from the lamp into as many different
distinct wavelengths as possible
= uses prisims or gratings
= grating more common: highly uniform and accurate etching patterns
= can have wavelength selection at less than 0.1 nm
PH meter - answer thin walled bulb of glass containing 0.1M HCL in contact with a
metal wire electrode.
in solution, potential is et up across thin glass wall
compares signal to signal in standard buffer solution
buffer effectiveness depends on – answer pH, concentration, volume and identity
buffer capability at different pH ranges - answer phosphate buffer
what colour is ONP - answer yellow
at 420 nm
Jablonski Diagram - answer An energy diagram that illustrates the electronic states of a
molecule and the transitions between them;
the states are arranged vertically by increasing energy and grouped horizontally by spin
multiplicity.
within any energy level (S) there are - answer additional different energy levels arising
from different vibrational states (V1,V2)
how long does absorption take
how long is molecules excited for - answer10^ -15 seconds
10^-12 seconds, excited e- returns to one of the vibrational rotational levels associated
with the ground state
=coupled with loss of heat
light source used depends on - answerwavelength instrument can operate at
consistency of light source intensity
wavelength output
durability
cost
monochromator - answerseparate the light emitted from the lamp into as many different
distinct wavelengths as possible
= uses prisims or gratings
= grating more common: highly uniform and accurate etching patterns
= can have wavelength selection at less than 0.1 nm
