How does the melting points of an impure sample of a substance compare to the melting point of a pure sample of the same substance?
a) The two melting points are the same but the impure sample has a broader range.
b) The two melting points are the same but the impure sample has a sharper range.
c) The impure sample has a higher melting point.
d) The impure sample has a lower melting point with a broader range.
e) The impure sample has a lower melting point with a sharper range.
