Organic analysis

• What are the two analytical techniques emphasized in the AQA AS specification unit 2?

  Mass spectrometry and infrared spectroscopy
• Why are mass spectrometry and infrared spectroscopy considered advanced techniques?

  They require extensive training and knowledge
• What type of questions are typically asked about mass spectrometry in exams?

  Application-type questions based on analysis
• What are the key components of a mass spectrometer?

  • Ionizer
  • Acceleration plates
  • Electromagnet
  • Detector
• What does the current produced in a mass spectrometer indicate?

  It is proportional to the abundance of isotopes
• What does the M/Z ratio represent in mass spectrometry?

  Mass over charge of ions detected
• What is the typical charge assumed for ions in mass spectrometry?

  +1
• How does a peak at M/Z 46 relate to ethanol in mass spectrometry?

  It corresponds to the molecular ion peak of ethanol
• What is the significance of the molecular ion peak in mass spectrometry?

  It indicates the molecular mass of the compound
• If a molecular ion peak is at M/Z 42, what is the molecular formula of the alkane?

  C3H6
• What is the general formula for alkanes?

  CnH2n
• How can high-resolution mass spectrometry differentiate between sulfuric acid and phosphoric acid?

  By providing precise atomic mass values
• What is the molecular mass of sulfuric acid calculated using precise atomic masses?

  98.06102
• What is the molecular mass of phosphoric acid calculated using precise atomic masses?

  97.97722
• What is the process of ionization in mass spectrometry?

  • High-energy electrons bombard the sample
  • Electrons are removed from molecules
  • Formation of molecular ions occurs
• What are the key differences between sulfuric acid and phosphoric acid in mass spectrometry?

  • Both have similar molecular masses at two significant figures
  • High-resolution measurements reveal distinct values
  • Allows differentiation based on precise atomic masses
• What is the first number mentioned in the study material?

  97
• What is the second number mentioned in the study material?

  97722
• What is the third number mentioned in the study material?

  98 06102
• What is the main operation performed with the numbers mentioned?

  Multiplication
• What year should students be able to perform the multiplication mentioned?

  Year seven
• What does mass spectrometry help to determine?

  Differences in molecular weights
• How many decimal places does the high precision in mass spectrometry provide?

  Five decimal places
• What is the main analytical technique discussed after mass spectrometry?

  Infrared spectroscopy
• What is the basic process of infrared spectroscopy?

  Shining infrared radiation on a sample
• What does the detector in infrared spectroscopy record?

  Transmitted infrared radiation
• What do bonds absorb in infrared spectroscopy?

  Specific ranges of infrared radiation
• What is provided to students during an exam for infrared spectroscopy?

  A table of wave numbers
• What does the infrared spectrum indicate about a sample?

  What bonds are present in the sample
• What are the downward peaks in an infrared spectrum called?

  Peaks
• What does the fingerprint region in an infrared spectrum indicate?

  Uniqueness of a compound
• How can the fingerprint region be used in analysis?

  To detect impurities in compounds
• What is the molecular formula of compounds R and S mentioned?

  C6H12
• What type of hydrocarbon is compound R?

  Unsaturated hydrocarbon
• What type of hydrocarbon is compound S?

  Saturated hydrocarbon
• What is the expected peak range for a carbon-carbon double bond?

  1620 to 1680
• How can one deduce the presence of a carbon-carbon double bond in a spectrum?

  By identifying a peak in the range
• What does the absence of a peak at 2850 to 3300 indicate?

  No CH bond present
• What is the significance of comparing two spectra?

  To identify compounds or impurities
• What is the main focus of questions related to infrared spectroscopy?

  Comparing two molecules or spectra