The Mass Spectrometer

Question 1

What are isotopes?

Answer 1

Isotopes are atoms of the same element with different numbers of neutrons and different masses.

Question 2

Why do all isotopes of an element react the same way?

Answer 2

Because they all have the same electron configuration.

Question 3

What does abundance tell us?

Answer 3

Abundance tells us how common each isotope is.

Question 4

How does a time of flight Mass spectrometer work?

Answer 4

1. Take a sample of the element that we ave interested in and place it into sample chamber.(sample contains all different isotopes of that element)
2. Atoms are then ionised ( converts au atoms into positive ions)
3. Ions are now attracted to a negatively charged plate. Negative charge causes the ions to accelerate which increases kinetic energy if the ions.
4. Once the ions pass through the negative plate they stop accelerating and drift down the chamber towards the detector.
5. Lighter ions move down the drift chamber faster than heavier ions.
6. At the end of the drift chamber, ions reach the detector.
7. When the ions reach the detector they cause a current to flow due to the transfer of electrons.
8. Size of current caused by atoms measures the abundance of the isotopes (more abundant isotope will create a greater current than a less abundant isotope.)

(INTERIOR OF MASS SPECTROMETER IS A VACCUM)