Interactive, scaffolded model
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The activity offers students an opportunity to manipulate the central variables in mass spectroscopy, which operates on the principle that moving ions may be deflected by a magnetic field and hence identified. This model demonstrates how the force exerted on each ion depends upon the strength of the magnetic field, the velocity with which the ion is moving, and its charge.
Students will be able to:
• separate the moving ions according to their mass-to-charge ratios;
• explain the role of the magnetic field in the deflection of moving ions;
• explain why the angle of deflection is proportional to the mass-to-charge ratio.
The angle of deflection in a mass spectrometer is proportional to the substance's mass-to-charge ratio.
Additional Related Concepts
to see examples of mass spectra of elements.
To see uses of mass spectroscopy, visit
A good general, though high level (AP or higher) introduction.