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Consider the following definitions: I. Isotopes: Having the same atomic number but a different mass number.  II. Isotones: Atoms of different elements having the same number of electrons.  III. Isobars: Same mass number but different atomic numbers  Which among the above is/are correctly matched?

Consider the following definitions: I. Isotopes: Having the same atomic number but a different mass number.  II. Isotones: Atoms of different elements having the same number of electrons.  III. Isobars: Same mass number but different atomic numbers  Which among the above is/are correctly matched? Correct Answer Both I and III 

  • Isotopes are elements which have the same atomic number but different mass number. Example- 6C12, 6C13 and 6C14. 
  • Isotones are elements which have the same number of neutrons. Examples- 30 Si14 and 31P15 .  
  • Isobars are elements which have the same mass number but different atomic numbers. Examples- 18Ar40, 19K40, 20Ca40. 
  • Therefore, only statements I and III are correct.

Related Questions

Which of the following statements is/are correct? 1. The atoms of an element having the same atomic number but a different mass number are called isotopes. 2. The nuclei which have the same mass number but a different atomic number are called isobars.
Which of the following pair is correct? I. Isotopes - The same atomic number but a different mass number  II. Isobars - The same mass number but a different atomic number.
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4. Elements in modern periodic table are arranged in increasing order of their atomic numbers.
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