2017 · Q16
There are two elements calcium (atomic number 20) and argon (atomic number 18), The mass number of both the elements is 40. They are therefore known as
General KnowledgeChemistry
- Aisotones
- Bisochores
- Cisobars
- Disotopes
Explanation
Same mass number (40) but different atomic numbers (20 vs 18) defines isobars. Isotopes share the atomic number; isotones share the neutron number (Ca-40 has 20 neutrons, Ar-40 has 22 — so they are not isotones). Hence C.