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1. I've recently been studying C4 in my Chemistry OCR GCSE textbook and, at the end it has a 'Grade Checker'. One of the criteria for an A* grade is:
'Understand the radius and mass of atoms'.
I've flipped back and tried to find the radius of atoms in the book but i can't find it anywhere. Any help would be appreciated
2. (Original post by hollys7717xx)
I've recently been studying C4 in my Chemistry OCR GCSE textbook and, at the end it has a 'Grade Checker'. One of the criteria for an A* grade is:
'Understand the radius and mass of atoms'.
I've flipped back and tried to find the radius of atoms in the book but i can't find it anywhere. Any help would be appreciated
It's in the physics A2 book.

https://en.wikipedia.org/wiki/Atomic_mass

Hopefully those help
3. It seems as though the criteria is asking for an understanding of the radius rather than the integer value of the radius. An appropriate answer would probably be: The radius of an atom is the distance from the nucleus to the outermost shell/energy level. Another answer could be that: 'the radii of atoms are so large that they are mainly comprised of air' or even 'the mass of the atom is due to the mass of the protons and neutrons. The radius of an atom is very large. As a result, the density of an atom is relatively low'.
4. atoms have a radius of 10^-10m and a mass of 10^-23g, if you have a CGP revision guide then it's on the first or second page of C4
5. (Original post by Vanilla Cupcake)
atoms have a radius of 10^-10m and a mass of 10^-23g, if you have a CGP revision guide then it's on the first or second page of C4
that is just a vague approximation, different atoms are gonna have different masses and radii
6. (Original post by hollys7717xx)
I've recently been studying C4 in my Chemistry OCR GCSE textbook and, at the end it has a 'Grade Checker'. One of the criteria for an A* grade is:
'Understand the radius and mass of atoms'.
I've flipped back and tried to find the radius of atoms in the book but i can't find it anywhere. Any help would be appreciated
different atoms have different radius and mass, for example, hydrogen is less dense and has smaller atoms than ununoctium. the further you go down the periodic table the heavier the atoms.
7. (Original post by Alexion)
that is just a vague approximation, different atoms are gonna have different masses and radii
true but those are the figures given by the ocr gcse spec which is what op was looking for

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