# How are molar and molecular mass of any compound numerically the same?

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#1
I can't find any answers anywhere.
1
2 years ago
#2
The molecular mass is the mass of one molecule of a substance, whereas the molar mass is the mass of one mole of a substance.

One mole of carbon-12 has a mass of 12g (the molar mass). The molecular mass of carbon-12 equals 12u (atomic mass units). This means if the know the mass of one molecule in atomic mass units you can find the molar mass easily by just putting the units as grams or vice versa.
0
2 years ago
#3
(Original post by alevelphysicist)
The molecular mass is the mass of one mole of a substance, whereas the molar mass is the mass of one mole of a substance.

One mole of carbon-12 has a mass of 12g (the molar mass). The molecular mass of carbon-12 equals 12u (atomic mass units). This means if the know the mass of one molecule in atomic mass units you can find the molar mass easily by just putting the units as grams or vice versa.
Molecular mass is a relative measurement comparing the mass of an average molecule of the compound to the mass of a standard atom of the isotope carbon-12. It has no units.
0
2 years ago
#4
(Original post by charco)
Molecular mass is a relative measurement comparing the mass of an average molecule of the compound to the mass of a standard atom of the isotope carbon-12. It has no units.
Okay I miss typed the definition and I’ve now corrected it.

Although it is compared to a standard atom of carbon-12, it’s still a mass and so must have units. 1 atomic mass unit is defined as 1/12th of the mass of one carbon-12 atom and so that’s the unit used for comparing other atoms to carbon-12.

Relative atomic mass has no units and so that's why there are no units on a periodic table.
0
2 years ago
#5
(Original post by charco)
Molecular mass is a relative measurement comparing the mass of an average molecule of the compound to the mass of a standard atom of the isotope carbon-12. It has no units.
Daltons no? The Dalton is the unit of atomic mass, molecular mass is the summed atomic mass of the compound.
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