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प्रश्न
Write the scientific reason.
The third period contains only eight elements even though the electron capacity of the third shell is 18
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उत्तर
- The current periodic table consists of seven horizontal rows, known as periods. Periodic elements are ordered in increasing order of atomic numbers. The third row consists of 8 elements, with an electron capacity of 18.
- During the third period, the atomic number and number of electrons in the shell rise as you move left to right. The number of elements in the third period is determined by electronic configuration and the octet rule.
Argon (Ar) is the final element of the third period with a maximum capacity of 18 electrons. The octet of electrons is full, and because argon belongs to the zero group, the third shell has 18 electrons.Atomic No. 11 12 13 14 15 16 17 18 Elements Na Mg Al Si P S Cl Ar
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संबंधित प्रश्न
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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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Which of the above elements has the highest metallic character?
An element has its electron configuration as 2, 8, 2. Now answer the following question.
What is the group of this element?
Which among the following elements would lose an electron easily?
Find the odd one out and give its explanation.
Answer the following question in one sentence.
What determines the chemical reactivity of elements?
Match the columns.
| Column A Electronic configuration |
Column B Valency |
| 1) 2, 2 | a) 1 |
| 2) 2, 8, 1 | b) 2 |
| 3) 2, 5 | c) 3 |
| d) 5 |
Match the columns.
| Column A | Column B |
| 1) Alkaline earth metals | a) Group 18 |
| 2) Alkali metals | b) Group 17 |
| 3) Halogen | c) Group 2 |
| 4) Noble gas | d) Group 1 |
| e) Group 14 |
Write the name.
Highest electropositive element
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- What is the atomic number of element A?
- Find the group to which this element belongs.
Distinguish between:
Group - Period
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- 2, 8, 2
- 2, 8, 7
- 2, 1
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 |
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- Which elements have the same column?
- Which elements are in the 18th column?
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- Which of the following elements A or B will form compounds?
Observe the periodic table given below and write the answers of the questions.

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- Classify the elements in this row as metal, nonmetal and metalloids.
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- Write name of any two metalloid elements.
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