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प्रश्न
Write a scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
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उत्तर
- Electronic configuration of boron is (2, 3). The electronic configuration of oxygen is (2, 6).
- Both boron and oxygen have electrons in the two shells, K and L.
- The elements with the same number of shells occupied by electrons belong to the same period.
Hence, boron and oxygen elements are placed in the second period in the periodic table.
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संबंधित प्रश्न
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
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Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with an explanation.
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An element has its electron configuration as 2,8,2. Now answer the following questions.
i. What is the atomic number of this element?
ii. What is the valency of this element?
iii. What is the group of this element?
iv. To which period does this element belong?
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`_7N , _4Be , _18Ar , _17CL`
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To which period does this element belong?
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Find the odd one out and give its explanation.
Answer the following question in one sentence.
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Write the name.
Highest electropositive element
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The group of elements having electronic configuration 2, 2.
Right or wrong sentence.
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Beryllium and calcium are alkaline earth metals.
Distinguish between:
Group - Period
Write name of elements, symbol, atomic number, electronic configuration of second period in modern periodic table?
Observe the given chart and answer the questions given below.
| Element | A | B | C | D |
| Electronic configuration | 2, 1 | 2, 8 | 2, 8, 1 | 2, 8, 8 |
- Which elements are in the same row?
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- Which elements are in the 18th column?
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Observe the periodic table given below and write the answers of the questions.
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- What is the atomic number of this element?
- What is the group of this element?
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