Wednesday, 13 February 2013

1.11 understand the terms atomic number, mass number, isotopes and relative atomic mass (Ar)

Atomic number: number of protons (the same as number of electrons.)

Mass number: number of protons + neutrons.

Isotopes: Atoms of an element with different numbers of neutrons.

Relative atomic mass (Ar): the mass of one atom of an element.

12 comments:

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  3. (the same number of neutrons)/ not electrons

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  5. (the same number of neutrons)/ not electrons

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  6. hi in the relative atomic mass one, do you have to mention something about in relation to carbon 12?

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  7. the way we learnt it was: the weighted mean mass of an atom of an element, relative to one twelfth of the mass of an atom of carbon-12. That got me all the marks in the exams

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  8. Ram is the average weighted mass between all the isotopes of an element

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  10. Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes.

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  11. AN ISOTOPE IS AN ATOM WITH THE SAME NUMBER OF PROTONS OR DIFFERENT NUMBER OF NEUTRONS

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  12. The Chemistry Syllabus has changed…

    Here is a New blog for the 2017 Syllabus:

    https://igcse-chemistry-2017.blogspot.hk/

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