- Concept Videos
- Solutions 58

Nuclei with the same number of *neutrons* but different mass numbers are called *isotones*. Write the symbols of four isotones of ^{236}Th.

Hey guys, so at this point I hopefully you guys know what an isotope is so we're familiar with the term isotope, isotopes have the same number of protons By different number of neutrons which is shown you can show as NO, now we also have a new term isotones, isotones have different number of protons but same number neutrons, here we need to figure out some Isotones of Thorium and here it'll be a thorium 236 and so here we want to have different number of protons for the same number of neutrons so good example here we should realize that thorium first of all has an atomic number of 90 when we subtract these 2 it gives me 146 so we have 146 neutrons, so we just have to figure out some elements that have different number of protons a different atomic number but same number of neutrons a good examples We could have protactinium when we subtract those numbers that gives me 146 so protactinium 237, who else? We could have Uranium 238 so Uranium 238 we could have Neptunium 239, so here when we subtract those that gives me those it gives me that so this is neptunium 239 then we could also have Plutonium 240 so here as you can see when we're subtracting it for all that we have different number of protons cause all of them have different atomic numbers but all of them have the same number of neutrons and this answer will be plutonium 240, some remember isotones are basically the opposite definition of isotope, isotopes have the same number of protons so theyÕre the same element they just have different number of neutrons, isotones are the opposite different number proton and they make different elements or what they have in common is that they all have the same number of neutrons.