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प्रश्न
From the symbol \[\ce{^4_2He}\] for the element helium, write down the mass number and the atomic number of the element.
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उत्तर
\[\ce{_{Atomic number} ^4_2He ^{mass number}}\]
- Mass number – 4
- Atomic number – 2
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संबंधित प्रश्न
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| X | Y | |
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| Neutrons | 6 | 8 |
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