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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
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 explanation.
11Na, 15P, 17Cl, 14Si, 12Mg Which of these has largest atoms?
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
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Which of this element belong to the period 3? Write their electronic configuration
`3^(Li) , 14^(Si) , 2^(He) , 15^(P)`
An element has its electron configuration as 2, 8, 2. Now answer the following question.
To which period does this element belong?
An element has its electron configuration as 2, 8, 2. Now answer the following question.
Which of the following elements would this element resemble?
(Atomic numbers are given in the brackets)
N(7), Be(4), Ar(18), Cl(17)
Which pair of atomic numbers represents elements in the same group?
Answer the following question in one sentence.
Write the name of the noble gas having 2 electrons in its valence shell.
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 |
The number of electrons in the outermost shell of an atom determines the ______.
Beryllium and calcium are alkaline earth metals.
Right or wrong sentence.
The number of shields decreases as the calculation goes down from top to bottom.
Write an explanation.
Group
Complete the following chart.
| Shell | n | 2n2 | Electron holding capacity |
| K | 2 × 12 | 2 | |
| L | 2 | 8 | |
| 3 | 2 × 32 | 18 | |
| N | 4 | 2 × 42 |
Find the period in which these elements can be placed.
4Be, 17Cl, 2He, 13Al
Electronic configuration of element A is 2,8,1. Answer the following questions based on this information.
- What is the atomic number of element A?
- Find the group to which this element belongs.
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?
- Which elements have the same column?
- Which elements are in the 18th column?
- Which element is more reactive among A and C?
- Which of the following elements A or B will form compounds?
