Struggling with your prescribed literature?
Our Literature Study Guides provide insights and analysis of themes and characters and includes guidelines for writing your exam.
nitrogen (N), phosphorus (P) and potassium (K)
the initial step needed to start polymerisation.
water containing salts of magnesium and calcium.
shows the structure of the molecule but not all the bonds between every atom.
a number that indicates how the atom will react during the formation of chemical bonds.
a measure of the number of bonds formed by an atom of a given element.