Which is a better unit for expressing molar mass, amu or grams/mole ?

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Solution

Answer
While the numeric values are the same the units convey different information.
Explanation :
The term amu refers to the atomic mass unit which is the value of a proton and the value of a neutron in regards to a mass comparison to the standard that carbon - 12 has 6 protons and 6 neutrons
When the designation for the the mass is $\frac{g r a m s}{m o l}$ the unit refers to the fact that in 1 mole of a substance there is a specific gram amount.
Let us look at an example of Carbon Dioxide - $C O_{2}$
The gram mass of of carbon dioxide $C O_{2}$ can be determined by combining the mass of one carbon atom and 2 oxygen atoms.
$C = 1 \times 12.01 = 12.01$
$O = 2 \times 15.99 = 31.98$
$12.0 + 31. 98 = 43.99$ grams
This value can be designated as $\frac{g r a m s}{m a s s}$ meaning that in one mole $(6.02 \times 10^{23})$ molecules ) there would be 43.99 grams of $C O_{2}$
However, if the unit is designated as amu the information informs us that there are 6 protons + 6 neutrons = 12 ma in carbon and 2(8 protons + 8 neutrons) = 32 amu in oxygen for a total of 44 amu in a $C O_{2}$

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