This Study Mind Tutorial covers the following specification points:

Edexcel: 2.13-2.15

2.13. know that electronegativity is the ability of an atom to attract the bonding electrons in a covalent bond

2.14. know that ionic and covalent bonding are the extremes of a continuum of bonding type and that electronegativity differences lead to bond polarity in bonds and molecules

2.15. understand that molecules with polar bonds may not be polar molecules and be able to predict whether or not a given molecule is likely to be polar