Question
Download Solution PDFThe mass number of an isotope of an element is 298. If its nucleus has 196 neutrons, what is its atomic number?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe correct answer is 102.0
Key Points
- An atomic number is defined as the number of protons present in the nucleus of an atom and is denoted by the letter 'Z'.
- The number of electrons is equal to the number of protons in an atom to maintain the electrical neutrality of the atom.
- So, Z = Number of Protons in the Nucleus = Number of electrons in an atom.
- The mass number is the total number of protons and neutrons or a total number of nucleons present in the nucleus of an atom and is denoted by the letter 'A'.
- So, Mass number, A = Number of Protons + Number of Neutrons, or
- The mass number, A = Atomic number + Number of neutrons.
- Given, the mass number of an isotope of an element is 298 and its nucleus has 196 neutrons.
- So, the atomic number is given by, Z = 298 - 196 = 102. Hence option 3 is correct.
Additional Information
- The Isotope of an element is defined as the atoms of an element having the same number of protons or electrons (atomic number) but a different number of neutrons (mass number).
- Examples of Isotopes are 11H (Protium), 12H (Deutirium), and 13H (Tritium).
- Polonium has the most number of Isotopes.
- Isotopes of an element have the same chemical properties but different physical properties.
- Isobars of the element is having the same mass number (A) but a different atomic number (Z).
- Artificial isobars are obtained by the emission of β-particles from radioactive elements.
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