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प्रश्न
Which of the following are isoelectronic species i.e., those having the same number of electrons?
Na+, K+, Mg2+, Ca2+, S2–, Ar
उत्तर
Isoelectronic species have the same number of electrons.
Number of electrons in sodium (Na) = 11
Number of electrons in (Na+) = 10
A positive charge denotes the loss of an electron.
Similarly,
Number of electrons in K+ = 18
Number of electrons in Mg2+ = 10
Number of electrons in Ca2+ = 18
A negative charge denotes the gain of an electron by a species.
Number of electrons in sulphur (S) = 16
∴ Number of electrons in S2- = 18
Number of electrons in argon (Ar) = 18
Hence, the following are isoelectronic species:
1) Na+ and Mg2+ (10 electrons each)
2) K+, Ca2+, S2– and Ar (18 electrons each)
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संबंधित प्रश्न
The composition of the nuclei of two atomic species X and Y are given as under
| X | Y | |
| Protons | 6 | 6 |
| Neutrons | 6 | 8 |
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Complete the following table.
| Atomic number | Mass number | Number of Neutrons | Number of protons | Number of electrons | Name of the Atomic species |
| 9 | - | 10 | - | - | - |
| 16 | 32 | - | - | - | Sulphur |
| - | 24 | - | 12 | - | - |
| - | 2 | - | 1 | - | - |
| - | 1 | 0 | 1 | 0 | - |
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Also, draw atomic diagrams for them.
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______ = No. of protons = No. of the electrons.
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