To convert atomic mass units (amu) to grams, you can use the conversion factor:
1 amu = 1.66053906660 x 10^-24 grams
To find the mass in grams of 16.5 amu, you can multiply 16.5 amu by the conversion factor:
16.5 amu x (1.66053906660 x 10^-24 grams/1 amu)
Calculating this expression, you will find:
16.5 amu x 1.66053906660 x 10^-24 grams/1 amu = 2.73588569959 x 10^-23 grams
Therefore, the mass in grams of 16.5 amu is approximately 2.73588569959 x 10^-23 grams.