Relative molecular mass using unified mass unit

AI Thread Summary
To calculate the relative molecular mass of krypton gas, the mass of a krypton atom is divided by the unified mass unit, resulting in a value of approximately 83 amu. This value is equivalent to the relative molecular mass, which is typically expressed in grams per mole. The discussion highlights a confusion regarding the units and definitions of molecular mass versus atomic mass. A chemistry teacher clarified that relative molecular mass is indeed represented in grams per mole. Understanding these distinctions is crucial for accurate calculations in chemistry.
jadoreux
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The problem
A bubble of kryptopn (Kr) gas is formed underwater. The bubble has a volume of 2.14x10-6m3 and contains 1.70x1020 krypton molecules each of mass 1.39x10-25kg. The pressure of the gas inside the bubble is 300kPa.

Calculate the relative molecular mass.The attempt at a solution

When i looked in the markscheme of this paper, the answer was Mr=1.39x10-25/1.66x10-27 as the answer. so does this mean to find the relative molecular mass i divide the mass by the unified mass unit?
 
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What you have calculated is the mass of a Krypton atom in amu (Atomic Mass Units)
= 83
 
is that the same as the relative molecular mass? what i worked out is what the markscheme had written as the result.
 
I have asked a chemistry teacher friend and he said relative molecular mass is given in grams per mole4
 

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