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Name: Cliff
Status: educator
Grade: 6-8
Location: VA
Country: N/A
Date: December 2006

While NIST and DOE list the Greek letter mu as the symbol for an atomic mass unit instead of amu, most educational sources at all levels and the EPA use the symbol amu. Do both mean the same thing and which should be used for secondary school chemistry?

Many times the atomic mass unit is shown as u. The correct SI unit is Daltons (Da).

Nathan A. Unterman

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