Topic 1 - Atomic Structure And The Periodic Table

Question 1

1) know the structure of an atom in terms of neutrons, protons and electrons.

Answer 1

Protons and neutrons make up the nucleus with electrons orbiting the nucleus in shells

Question 2

Know the structure of an atom in terms of electrons, protons and neutrons.

Answer 2

Protons and neutrons are found in the nucleus of the atom. Electrons orbit the nucleus in shells.

Question 3

Know the relative mass and relative charge of protons, neutrons and electrons.

Answer 3

Protons: 1, +1
Neutrons: 1, 0
Electrons: 1/1836, -1

Question 4

Know what is meant by the terms “atomic (proton) number” and “mass number”

Answer 4

Atomic number = the number of protons and electrons in an atom
Atomic mass = the number of protons AND neutrons

Question 5

Understand the term “isotopes”

Answer 5

Isotopes = variants of the same element, with the same atomic (proton) number and different atomic masses. OR the same number of protons and a different number of neutrons.

Question 6

Be able to define the terms “relative isotopic mass” and “relative atomic mass”, based on the 12C scale.

Answer 6

Relative isotopic mass = the mass of an atom of an element relative to one twelfth of the mass of an atom of carbon-12

Relative atomic mass = the weighted average mass of an atom of an element relative to a twelfth of an atom of carbon-12

Question 7

How to calculate relative atomic mass

Answer 7

RAM = (atomic mass x abundance) / 100

Question 8

Relative molecular mass vs relative formula mass

Answer 8

Relative formula mass is the total mass of all elements in a compound whilst relative molecular mass the sum of all the relative atomic masses of the atoms in a molecule

Question 9

Be able to analyse and interpret data from mass spectrometry to calculate relative atomic mass from relative abundance of isotopes.

Answer 9

Same as calculating RAM. But using data form a graph

Question 10

Be able to predict the mass spectra, including relative peak heights, for diatomic molecules, including chlorine

Answer 10

(Chlorine example)
1) find ratio of first peaks (35 and 37)
2) then find the ram with them
3) to find the relative heights of the 2nd peaks (70, 12, 74) you first find which of 35 and 37 makes up each number.
4) find the ratios of these relative heights by finding the probability of having each peak.
You should get 9:6:1

Question 11

Understand how mass spectrometry can be used to determine the relative molecular mass of a molecule limited to the m/z values for the molecular ion M+, giving the relative molecular mass of the molecule.