# Difference between Molar Mass and Molecular Mass and Atomic Mass??

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#1
Hi guys,
Got so confused about the difference between these masses, Any help??
0
1 year ago
#2
Yo. So the molar mass is the mass of one mole or however many there are eg. Avogadro’s constant or moles=mass/Mr.
Molecular mass is Mr which is all of the ATOMIC masses of the given compound/element added together. Atomic mass is the number of protons and neutrons added together
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1 year ago
#3
(Original post by Tintin1912)
Yo. So the molar mass is the mass of one mole or however many there are eg. Avogadro’s constant or moles=mass/Mr.
Molecular mass is Mr which is all of the ATOMIC masses of the given compound/element added together. Atomic mass is the number of protons and neutrons added together
Not quite.

The term "atomic mass" usually means relative atomic mass, which is the weighted average of all of the isotopes of the element on a relative scale whose base is 12C = 12.0000

You are defining "mass number" which is the sum of protons and neutrons in a specific isotope of an element.
0
1 year ago
#4
(Original post by Sara_Acton)
Hi guys,
Got so confused about the difference between these masses, Any help??
(Relative) Atomic mass is the average weight of an atom of a specific element, proportional to the percentage abundance of each of its naturally occurring isotopes, using that the mass of a C12 atom is 12.000 perfectly.
Molecular mass is the total atomic masses of all atoms of a compound added together. Water = H2O, = 16 +1 +1 = 18.
Molar mass or the mass number is the total of the protons and neutrons added together for a specific atomic isotope of an element, found on the periodic table as the number closest to the top of the box.
0
1 year ago
#5
(Original post by charco)
Not quite.

The term "atomic mass" usually means relative atomic mass, which is the weighted average of all of the isotopes of the element on a relative scale whose base is 12C = 12.0000

You are defining "mass number" which is the sum of protons and neutrons in a specific isotope of an element.
Oh lol that’s actually a very helpful clarification thanks.
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