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प्रश्न
Distinguish between:
Group 17 - Group 18
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उत्तर
| Sr. No. | Group 17 | Group 18 |
| 1. | Elements of group 17 are called halogens. | Elements of group 18 are called inert gas elements or noble gases. |
| 2. | They have seven valence electrons. | They have eight valence electrons, except helium, which contains 2 electrons. |
| 3. | Their valency is 1. | Their valency is zero. |
| 4. | They form diatomic molecules with the general formula (X2). | They are monoatomic gases under normal conditions. |
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संबंधित प्रश्न
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(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
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(i) same atomic mass
(ii) same atomic number
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(c) (ii) and (iii)
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(b) valency
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Transition element
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Name the following metal:
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