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प्रश्न
Find the odd one out and give its explanation.
विकल्प
Beryllium
Magnesium
Carbon
Oxygen
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उत्तर
Magnesium
Explanation-
Magnesium is placed in period 3 while others are placed in period 2 of the modern periodic table.
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संबंधित प्रश्न
Which among the following elements would lose an electron easily?
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name of an element having electronic configuration 2,8,2.
What determines the chemical reactivity of elements?
Match the columns.
| Column A | Column B |
| 1) s -block | a) Lanthanides and actinides |
| 2) p -block | b) Group 3 to 12 |
| 3) d -block | c) Group 1, 2 |
| 4) f -block | d) Group 13 to 18 |
| e) Zero group |
Match the columns.
| Column A | Column B |
| Electronic configuration |
Valency |
| 1) 2, 2 | a) 1 |
| 2) 2, 8, 1 | b) 2 |
| 3) 2, 5 | c) 3 |
| d) 5 |
Write the name.
Highest electropositive element
Write the name.
The group of elements having electronic configuration 2, 2.
Beryllium and calcium are alkaline earth metals.
The number of shells decreases in a group from top to bottom.
Write scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
In group 2, beryllium and calcium elements, calcium is more electropositive element than beryllium.
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.
Identify periods of elements and blocks of elements from given electronic configuration?
- 2, 8, 2
- 2, 8, 7
- 2, 1
XY compound is formed by X (Atomic number 11) and Y (Atomic number 17), then answer the questions given below.
- Determine the position of the element X and Y periodic table.
- X and Y belongs to which of the following: metals, nonmetals or metalloids?
- From which block the elements X and Y are?
- Determine the electronic configuration and valency of these elements.
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.
What is the electronic configuration of K19?
An element has its electron configuration as 2, 8, 1. Now answer the following questions:
- What is the atomic number of this element?
- What is the group of this element?
- To which period does this element belong?
