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Isotopes

Can someone explain isotopes to me GCSE Level thanks.
Reply 1
Atoms with same number of protons but different number of neutrons.
Original post by Silent_Ihsassin
Can someone explain isotopes to me GCSE Level thanks.

Say you have two versions of chlorine right?
So chlorine one will have the atomic number of 17. The atomic number is the same as the number of protons. So it would have 17 protons.
Chlorine two will ALSO have 17 protons. With isotopes, the proton number(atomic number) IS ALWAYS THE SAME. However, now comes neutrons. Neutrons and protons together make up the mass number of an element. So in isotopes they will have different neutron numbers, therefore this affects the atomic mass. So Chlorine one would have lets say 18 neutrons which makes the atomic mass 35. Chlorine two would have 19 neutrons which would make the atomic mass 36. So it is ATOMS WITH THE SAME NUMBER OF PROTONS BUT DIFFERENT NUMBER OF NEUTRONS.
Hope that helps:smile:
(edited 3 years ago)
Thanks
Original post by Luwei
Atoms with same number of protons but different number of neutrons.


An extraordinary good and short answer! :yes:

Original post by Silent_Ihsassin
Thanks

Can I add some another informations to it? as the nucleus has no difference in number of protons, but neutrons, the mass of the nucleus is instable and begin to decay. Thus isotopes are radioactive.

I thought that this is a useful knowledge for you, even for GCSE. Or could be at higher levels...
Original post by Kallisto
An extraordinary good and short answer! :yes:


Can I add some another informations to it? as the nucleus has no difference in number of protons, but neutrons, the mass of the nucleus is instable and begin to decay. Thus isotopes are radioactive.

I thought that this is a useful knowledge for you, even for GCSE. Or could be at higher levels...

that's a higher level answer... ll that GCSE level looks for is that isotopes are atoms of the same element, whereby the number of protons and electrons stay the same, but the number of neutrons and therefore the atomic mass vary.
Reply 6
Original post by Kallisto
Thus isotopes are radioactive.

There are, though, quite a few isotopes that are not radioactive.

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