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प्रश्न
Define periods of modern periodic table.
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उत्तर
The horizontal rows are called periods. The table consists of 7 periods, numbered from 1 to 7 from top to bottom.
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संबंधित प्रश्न
In the Modern Periodic Table, which are the metals among the first ten elements?
In the Modern Periodic Table, calcium (atomic number 20) is surrounded by elements with atomic numbers 12, 19, 21, and 38. Which of these have physical and chemical properties resembling calcium?
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Write the merits of the modern periodic table over Mendeleev’s Periodic table
Fill in the following blank with suitable word:
Group 17 elements are known as ...............
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Ca, Cl, Na, I, Li, Ba, Sr, K, Br
Separate these elements into three groups (families) of similar properties. State one property in each case on the basis of which you have made your choice.
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What is the fundamental difference in the electron configurations between the group 1 and group 2 elements?
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The tabular arrangement of elements in horizontal rows and vertical columns _________
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Give its electronic configuration
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- Their metallic characters
- Formation of their oxides
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Give the chemical formula of calcium phosphate
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Right or wrong sentence.
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An element which is an essential constituent of all organic compounds belongs to
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| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
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