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प्रश्न
Give a reason for the following:
A transition from metallic to non-metallic elements is seen on moving from left to right in a period of the periodic table.
उत्तर
In a period valence electrons increase from 1 to 7. But the shell remains the same. The element having valence electron 1, 2, 3 loose electrons, and are metals on the left. And elements having 5, 6, 7 valence electrons gain electrons and become non – metals are on the right of the periodic table.
Hence the transition from metallic to non-metallic character is seen from left to right a period.
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संबंधित प्रश्न
Write the number of horizontal rows in the modern periodic table. What are these rows called?
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An element X belong to 4th period and 17th group, state.
name of the element.
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| Elements | Atomic Radius (pm) |
| O | 66 |
| B | 88 |
| C | 77 |
| N | 74 |
| Be | 111 |
| Li | 152 |
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- State the period to which the above elements belong.
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Arrange the following in order of increasing radii:
N, O, P
With reference to the variation of properties in the Periodic table, which of the following is generally true?
Fill in the blank and rewrite the completed statement:
________ group in the periodic table contains elements that are all gases at room temperature.
