2.1 Atomic structure and isotopes

Question 1

Relative mass of an electron

Answer 1

1/1836

Question 2

Define isotope

Answer 2

Atoms of the same element with the same number of protons but a different number of neutrons and therefore different masses

Question 3

Why do isotopes of the same element have similar chemical properties?

Answer 3

They have the same number of electrons so the electron configuration remains the same which causes little/no effect of its properties

Question 4

What is the difference between an anion and cation?

Answer 4

Anion = negative ion
Cation = positive ion (purrsitive)

Question 5

Define relative isotopic mass

Answer 5

mass of an atom of an isotope compared with 1/12th of a carbon-12 atom

Question 6

Define relative atomic mass

Answer 6

weighted mean mass of an atom of an element compared with 1/12th of a carbon-12 atom

Question 7

Mass spectrometry steps

Answer 7

1. Sample placed inside
2. Sample is vapourised and then ionised using an electron beam
3. Ions are accelerated and deflected by magnets
4. Ions are separated due to their size and then detected
5. Each ion at the detector adds to the signal

Question 8

How do you find molecular mass on a mass spectrograph?

Answer 8

read the mass-charge ration of the final peak

Question 9

Formula to calculate relative atomic mass from mass spectrometer or from relative isotopic masses

Answer 9

(m/z1 x abundance) + (m/z2 x abundance)
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100 if abundance is a percentage
or total abundance added up (heights of peaks)