Topic 1 - Atomic Structure and
the Periodic Table
The Atom
Define the term isotope
atoms of the same element with a different number of neutrons
Why do different isotopes of the same element react in the same way?
because neutrons have no impact on chemical reactivity
reactions involve electrons and isotopes have the same number of electrons in
the same arrangement
Why is an atom neutral
becuase they have the same number of protons and electrons
What change happens across each period?
elements change from non metals to metals
Relative Mass
Topic 1 - Atomic Structure and the Periodic Table 1
, Define relative atomic mass
The weighted mean mass of an atom of an element compared with one twelth
of an atom of carbon-12
Define relative isotopic mass
The mass of an atom of an isotope compared with one twelth of the mass of an
atom of carbon-12
What assumptions are made when calculating the mass number
contribution of the electron is neglected
mass of both proton and neutron is taken as 1.0
What is the avagadros constant the number of?
its the number of atoms contained in one mole of any monatomic element
Electronic Structure
Describe the structure, forces and bonding in every element across period 2
Lithium and beryllium
giant metallic (structure)
strong attraction between +ions and delocalised electrons (forces)
metallic bonding (bonding)
Boron and carbon
giant covalent (structure)
strong interatomic forces of attraction between atoms (forces)
covalent bonding (bonding)
nitrogen, oxygen, fluorine and neon
simple molecular (structure)
weak intermolecular forces between molecules (forces)
covalent bonds within molecules and intermolecular forces between
molecules (bonding)
Topic 1 - Atomic Structure and the Periodic Table 2