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प्रश्न
Calculate the valency of element X whose atomic number is 9.
उत्तर
The electronic configuration of element X with atomic number 9 is 2,7
Its valency = 8−7 =1 Hence, the valency of element with atomic number 9 is 1.
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संबंधित प्रश्न
Write the number of periods the Modern Periodic Table has. State the changes in valency and metallic character of elements as we move from left to right in a period. Also state the changes, if any, in the valency and atomic size of elements as we move down a group.
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1) State the period and group to which Z belongs
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3) State the formula between Z and hydrogen
4) What kind of a compound is this?
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| Elements | Least atomic radius | Chemically least reactive |
| (i) F, Cl, Br (ii) Li, Na, K |
.................... .................... |
.................... .................... |
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The similarities in the properties of a group of elements are because they have the same …………………
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| Li | Be | B | C | O | F | Ne |
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The position of elements A, B, C, D and E in the periodic table are shown below:
|
Group 1 |
Group 2 |
Group 17 |
Group 18 |
|
|
|
|
D |
|
|
B |
C |
|
|
A |
|
|
E |
Which type of ion will be formed by elements A, B, and C.
State the following:
The group to which the element with an electronic configuration of 2, 8, 2 belongs.
