spectrophotometry

• Substance emissions:

  copper & barium - green

  calcium - orange

  potassium - purple

  lithium & strontium - red

  sodium - yellow
• spectrophotometry - light measurement
• spectrophotometer - can measure light and change in temperature
• monochromatic light - can emit 1 color only
• cuvette - can be round; no to cleaning agents, yes to mild detergent and water
• photomultiplier tube - produces electrical energy or voltage energy
• photodiode arrays - 5 volts
• vacuum and gas diode - photosensitive cathode; small amounts of gas (neon/argon)
• wavelength accuracy - didymium filter = 585 nm

  photometric accuracy - nickel sulfate = 510 nm

  cobalt chloride peak = 510 nm
• baseline stability - starting point; initial measurement

  arbitrary wavelength - random/no basis; 0 = arbitrary number ; 2% over 1 minute

  stray light & extraneous light - unwanted lights