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प्रश्न
Which of the following are true for an element?
- Atomic number = number of protons + number of electrons
- Mass number = number of protons + number of neutrons
- Atomic mass = number of protons = number of neutrons
- Atomic number = number of protons = number of electrons
पर्याय
(i) and (ii)
(i) and (iii)
(ii) and (iii)
(ii) and (iv)
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उत्तर
(ii) and (iv)
Explanation -
Mass number = p + n
Atomic number = p = e
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संबंधित प्रश्न
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| X | Y | |
| Protons | 6 | 6 |
| Neutrons | 6 | 8 |
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______ = No. of protons = No. of the electrons.
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| Column A | Column B | ||
| 1. | Mass of proton | a. | +1 |
| 2. | Mass of electron | b. | -1 |
| 3. | Charge of electron | c. | 9.31 x 10-28g |
| 4. | Charge of proton | d. | 1.67 x 10-24g |
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