The file elements_TmTb.csv contains the values of the melting points and boiling points of the elements. Make a scatter plot of these data, colouring the markers differently for metals and non-metals. Also annotate the plot to indicate the element carbon and the element with the greatest difference between its melting point and boiling point.
For the purposes of this exercise, the non-metallic elements may be taken to be those given in the following list.
nonmetals = ['H', 'He', 'C', 'N', 'O', 'F', 'Ne', 'S', 'P',
'Ar', 'Se', 'Cl', 'Kr', 'Br', 'Xe', 'I', 'Rn']