Acetaminophen Melting Point: Range & Impurity Effects

Most commonly sold under the names Tylenol in the U.S. and Canada and Paracetamol in the UK, acetaminophen is used to relieve pain and reduce fever. In solid form, acetaminophen is a white, crystalline powder with a slightly bitter taste.

Range

• The melting point range of acetaminophen is 304.2 to 309.6 degrees Fahrenheit.

Crude Vs. Pure

• The melting point of acetaminophen is always lower when containing impurities. In fact, chemists use the melting point of an acetaminophen sample to determine its purity content. Crude acetaminophen can be made by assembling its raw ingredients in a flask and placing it in hot water. Pure acetaminophen is made when you recrystallize the crude acetaminophen by heating the crude mixture, then cooling and collecting the newly formed crystals.

Method

• Chemists use a melting point apparatus filled with recrystallized acetaminophen to determine its melting point. The low end of the range seems to stay constant at 304.2 degrees Fahrenheit, but reports disagree on the upper range, some putting it closer 309.6 degrees Fahrenheit.