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प्रश्न
Name or state following with reference to the elements of the first three periods of the periodic table.
A metalloid in period 2 and in period 3.
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उत्तर
Metalloid in period 2 is B (Boron) and in period 3 is Si (Silicon)
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संबंधित प्रश्न
Calculate the number of gram atoms in 4.6 grams of sodium (Na = 23)
In the following set of elements, one element does not belong to the set. Select this element and state why it does not belong:
Oxygen, Nitrogen, Carbon, Chlorine, Fluorine
Name the element which is in first group and third period.
Rewrite the following statement after correction, if necessary:
Elements in the same period have equal valency
Taking into consideration the period of the elements given below, answer the following questions:
| Elements | Atomic Radius (pm) |
| O | 66 |
| B | 88 |
| C | 77 |
| N | 74 |
| Be | 111 |
| Li | 152 |
- Arrange the above elements in decreasing order of their atomic radii.
- State the period to which the above elements belong.
- Why this arrangement of elements is similar to the above period of modern periodic table?
- Which of the above elements have the biggest and the smallest atom?
- What is the periodic trend observed in the variation of atomic radius while going from left to right within a period?
Fill in the blank
Most electropositive elements belong to ______ group.
How many elements are there in period 2?
Choose the correct answer from the choice given:
An element A belonging to Period 3 and Group II will have
Moving left to right in the second period, the number of valence electrons _____.
Write the electronic configuration of two elements A and B whose atomic numbers are 20 and 17 respectively. Write the molecular formula of the compound formed when element A reacts with element B. State whether this compound is acidic, basic or neutral. Give a reason to justify your answer.
