What defines two elements as isobars?
Same mass number but different atomic numbers
Isobars are atoms of different elements that have the same mass number (total protons + neutrons) but different atomic numbers (different number of protons). For example, argon-40 (Z = 18) and calcium-40 (Z = 20) both have mass number 40, yet they are distinct elements.
"Same number of electrons" describes a neutral atom only in terms of its protons; equal electron count would mean the same atomic number, which would make them the same element, not isobars.
"Same number of neutrons" defines isotones, not isobars.
"Same atomic number" defines isotopes (same element, different mass numbers), which is the opposite condition.
Hence, two elements are isobars when they have the same mass number but different atomic numbers.
Similar Questions
Which of the following statements is correct about the size of atoms?
Atoms of different elements with different ___________ numbers but the same ______ number are known as isobars.
Important Questions from Structure of Atom
According to J.J. Thomson model of atom, positive charge is - Idenfity
- How many moles of He atoms are present in its 20 u mass ?
Which of the following electron transition in hydrogen atom will require largest amount of energy?
A species having 8 electrons in the third shell is very reactive while the other species having 8 electrons in the third shell is very inactive they are :
Which of the following is the general formula for saturated hydrocarbons?
