Atomic Mass Unit

Question

Earlier,the definition of one atomic mass unit was that it was equal to the mass of one Hydrogen atom. Later, it was changed to one-eighthn of an Oxygen atom. Yet, presently, it is that it is equal to one-twelth of the mass of one Carbon atom. What is the reason of these changes in definitions?

SAGAR SINGH - IIT DELHI · Accepted Answer

Dear pallabhi, The unified atomic mass unit replaced the atomic mass unit (chemical scale) and the atomic mass unit (physical scale), both having the symbol amu. The amu (physical scale) was one-sixteenth of the mass of an atom of oxygen-16. The amu (chemical scale) was one-sixteenth of the average mass of oxygen atoms as found in nature. 1 u = 1.000 317 9 amu (physical scale) = 1.000 043 amu (chemical scale) Please feel free to ask your queries here. We are all IITians and here to help you in your IIT JEE preparation. All the best. Win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian. Now you score 5+15 POINTS by uploading your Pic and Downloading the Askiitians Toolbar respectively : Click here to download the toolbar.. Askiitians Expert Sagar Singh B.Tech, IIT Delhi

Physical Chemistry> Atomic Mass Unit...

Earlier,the definition of one atomic mass unit was that it was equal to the mass of one Hydrogen atom. Later, it was changed to one-eighthn of an Oxygen atom. Yet, presently, it is that it is equal to one-twelth of the mass of one Carbon atom. What is the reason of these changes in definitions?

Pallabi Mishra , 15 Years ago

SAGAR SINGH - IIT DELHI

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Physical Chemistry> Atomic Mass Unit...

Earlier,the definition of one atomic mass unit was that it was equal to the mass of one Hydrogen atom. Later, it was changed to one-eighthn of an Oxygen atom. Yet, presently, it is that it is equal to one-twelth of the mass of one Carbon atom. What is the reason of these changes in definitions?

Pallabi Mishra , 15 Years ago

SAGAR SINGH - IIT DELHI

Provide a better Answer & Earn Cool Goodies

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