Summary:
- Isotopes are atoms that have the same atomic number, but different mass numbers due to a change in the number of neutrons.
- Carbon has three natural isotopes, while some heavier elements can have many more.
- Most elements naturally consist of mixtures of isotopes.
- Carbon-13 behaves chemically in exactly the same way as the more plentiful carbon-12.
- Tin has ten stable isotopes,.
- the most of any element.
- An isotope of barium (atomic number 56) has an mass of 138.
- How many neutrons are in the nucleus of this isotope?