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प्रश्न
The number of electrons in the atom of an element X is 15 and the number of neutrons is 16. Which of the following is the correct representation of an atom of this element ?
विकल्प
`""_15^31"X"`
`""_16^31"X"`
`""_15^16"X"`
`""_16^15"X"`
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उत्तर
`""_15^31"X"`
In an atom, the number of electrons is equal to number of protons ,which in turn is equal to the atomic number of the element. Also, the sum of number of protons and neutrons represents the mass number of the element. Therefore, the correct option is (a).
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संबंधित प्रश्न
Explain the Atomic number with example.
TRUE \ FALSE
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Match the statements in List I with the correct answer from List II.
| List I | List II |
| 1. Mass number of an atom is the number of protons and | A: Electron |
| 2. The sub-atomic particle with a negligible mass. | B: Argon |
| 3. An atom having stable electronic configuration. | C: Nitrogen |
| 4. A molecule formed by sharing of electrons [covalency] | D: Sodium |
| 5. A metallic atom having unstable electronic configuration. | E: Neutrons |
A ______ number describes a specific aspect of an electron.
‘A’ is denoted by ______.
Match the following:
| 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 |
In which one of the following, the number of protons is greater than the number of neutrons but number of protons is less than the number of electrons?
