Question

In: Chemistry

Melting point of ferrocene = 171.5-172.6 degrees Celcius Literature melting point of ferrocene = 172-174 degrees...

Melting point of ferrocene = 171.5-172.6 degrees Celcius

Literature melting point of ferrocene = 172-174 degrees Celcius

Melting point of acetylferrocene = 78.9-83.2 degrees Celcius

Literature melting point = 81-81 degrees Celcius

What do these melting points indicate about the purity and identity of the ferrocene and acetylferrocene samples?

Solutions

Expert Solution

  • A pure compound has a narrow range of melting point, usually 1-2oC.
  • However, a range of more than 3oC suggests the presence of one or more soluble impurities with the compound.
  • In the above two cases, the observed melting point of both, ferrocene and acetylferrocene have broad range of more than 3oC which suggests that they have the presence of soluble impurities and the compounds are not absolutely pure.
  • Although, not completely pure, the two compounds are ferrocene and acetyl ferrocene respectively along with a small amount of soluble impurities.
  • This happens as the impurities reduce the orderedness of the crystal lattice due to which a sharp melting point is not observed.

Thank You!


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