ePrivacy and GPDR Cookie Consent by TermsFeed Generator

Mass Spectrometry Quiz

Mass Spectrometry Quiz

Test your knowledge on mass spectrometry and its history

Thank you for taking our quiz!

Your score: /10
  • 1.
    Which element has the largest number of stable isotopes?

    Your answer:
    Correct answer:
    Naturally occurring tin is a mixture of its ten stable isotopes and they are found in the percentages as follows: 112Sn (1.0 %), 114Sn (0.7 %), 115Sn (0.3 %), 116Sn (14.5 %), 117Sn (7.7 %), 118Sn (24.2 %), 119Sn (8.6 %), 120Sn (32.6 %), 122Sn (4.6 %), and 124Sn (5.8 %). Molybdenum has six stable isotopes, ytterbium seven.
  • 2.
    The quadrupole mass filter has been known since the mid-1950s thanks to the work of Wolfgang Paul. The motion of ions in a quadrupole field can be described by solving second-order differential equations. When were these equations solved mathematically?

    Your answer:
    Correct answer:

    The solution of differential equations of this type came from the French mathematician Émile Léonard Mathieu (1835-1890), who studied the mechanical vibrations of the elliptical drumheads.

  • 3.
    What principle of positive ray detection was used in the first Thomson's parabola spectrographs?

    Your answer:
    Correct answer:

    In the spectrographs used by Thomson until 1910, the rays of positive electricity were detected by the phosphorescence they produced on a willemite screen. The screen was made by grinding rare zinc mineral willemite into a fine powder. After shaking in alcohol, the suspension was allowed to deposit slowly on a glass plate. Later, a photographic plate inside the spectrograph was used for more sensitive detection.

  • 4.
    What is the electric charge of an ion with m/z = m?

    Your answer:
    Correct answer:

    The particle carries one elementary charge, the value of which is 1.602 176 634 × 10−19 C (exactly).

  • 5.
    Who first reported the fragmentation after the gamma hydrogen rearrangement to an unsaturated group via a sixmembered intermediate?

    Your answer:
    Correct answer:
    It was first reported by Australian A. J. C. Nicholson in 1954 (Trans. Faraday Soc. 50: 1067-1073). The reaction description was published five years later (Anal. Chem. 1959, 31: 82–87) by the American chemist Fred McLafferty, by whose name we now refer to the rearrangement (McLafferty rearrangement).
  • 6.
    Which mass spectrometer was carried by the American spacecraft Viking 1 sent to the planet Mars in 1975?

    Your answer:
    Correct answer:
    Viking 1 carried two mass spectrometers, both equipped with double-focusing analyzers and electron ionization sources. The first spectrometer with a Mattauch-Herzog geometry was designed by Alfred Nier; it was intended to analyze the upper atmosphere of Mars. The second one with a Nier- Johnson geometry was part of the GC/MS apparatus designed by Klaus Biemann. It was used to analyze the regolith and the atmosphere at the landing site.
  • 7.
    What is the trajectory of a charged particle moving parallel to a uniform electric field in a vacuum?

    Your answer:
    Correct answer:

    If a positive charge is moving in the same direction as the electric field vector the particle's velocity will increase. If it is moving in the opposite direction it will decelerate. If a negative charge is moving in the same direction as the electric field vector the particle will decelerate. If it is moving in the opposite direction it will accelerate.

  • 8.
    What ionization technique was used for the first sequencing of peptides by mass spectrometry?

    Your answer:
    Correct answer:

    Mass spectrometry was used to sequence peptides for the first time in 1959 when K. Biemann described an innovative method based on the reduction of small peptides to polyamino alcohols with characteristic EI spectra. [https://doi.org/10.1021/ja01518a069]

  • 9.
    List these compounds according to their increasing mass: hydrazine (H4N2), oxygen (O2), methanol (CH4O).

    Your answer:
    Correct answer:

    The monoisotopic masses of these compounds are 31.989829 Da (oxygen), 32.026215 Da (methanol), and 32.037448 Da (hydrazine).

  • 10.
    Mass spectrometers known as calutrons were used for the industrial separation of uranium isotopes during the Manhattan Project. A large amount of copper was needed to make their magnetic coils. How was the highly-valued metal obtained during the war?

    Your answer:
    Correct answer:

    During the war, copper was preferably used for the production of brass shell casings and it was not available for the construction of calutrons. The designers came up with the idea of replacing copper with silver. They borrowed about 13,300 tons of silver from the West Point Bullion Depository in West Point, NY. After the war, the silver was returned to the Treasury with virtually no loss.

This website uses cookies to ensure you get the best experience on our website.

Agree