13. Which statement best describes an element? * O any combination of two or more atoms of different types
a pure substance made up of only one kind of atom
O
a substance containing only water molecules
O any kind of crystal

Substance a is a nonpolar liquid and has only dispersion forces among its constituent particles. substance b is also a nonpolar liquid and has about the same magnitude of dispersion forces among its constituent particles. when substance a and b are combined, they spontaneously mix.