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प्रश्न
An element has its electron configuration as 2, 8, 2. Now answer the following question.
What is the atomic number of this element?
The electronic configuration of an element is 2, 8, 2. Then write the answer to the question given below.
What is the atomic number of this element?
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उत्तर
The atomic number of this element is 12.
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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 an explanation.
13Al, 14Si, 11Na, 12Mg, 16S
Which of the above elements has the highest metallic character?
Write the scientific reason.
The third period contains only eight elements even though the electron capacity of the third shell is 18
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?
v. With which of the following elements would this element resemble?
`_7N , _4Be , _18Ar , _17CL`
Which of this element belong to the period 3? Write their electronic configuration
`3^(Li) , 14^(Si) , 2^(He) , 15^(P)`
Which pair of atomic numbers represents elements in the same group?
Which among the following is the largest element?
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 | 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 |
Right or wrong sentence.
The valency of the elements in group 2 is 1.
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
Write a scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
Find the period in which these elements can be placed.
4Be, 17Cl, 2He, 13Al
Observe the periodic table given below and write the answers of the questions.
- Write the name and valencies of the elements in 3rd row.
- Classify the elements in this row as metal, nonmetal and metalloids.
- Which block does nonmetals belong to?
- Write name of any two metalloid elements.
Make a chart which shows the name of the element, valency, atomic number, electronic configuration in the 2nd row of the modern periodic table and arrange these elements in ascending order of atomic mass.
