How to find the period ,block and group of an element by it's atomic n...
Introduction:
To find the period, block, and group of an element based on its atomic number, we need to understand the structure of the periodic table. The periodic table is organized in a way that allows us to determine these properties of an element.
Period:
The period of an element refers to its position in the horizontal rows of the periodic table. Each row is numbered from 1 to 7. The period number corresponds to the highest energy level (or shell) that contains electrons in the element's atom. For example, elements in the first row (period 1) have their electrons in the first energy level, while elements in the second row (period 2) have their electrons in the second energy level, and so on.
Block:
The block of an element indicates the type of subshell that contains the last electron added to the electron configuration of that element. There are four blocks in the periodic table: s, p, d, and f.
Group:
The group of an element refers to its position in the vertical columns of the periodic table. The group number represents the number of valence electrons an element has. Elements in the same group often exhibit similar chemical properties due to their shared number of valence electrons.
Steps to find the period, block, and group:
1. Determine the atomic number of the element you want to find the properties for.
2. Identify the period of the element by looking at its atomic number. For example, if the atomic number is 12, the element belongs to period 3 because it falls between atomic numbers 11 and 18.
3. Find the block of the element based on its atomic number:
- Elements in s-block have their last electron in the s-subshell. This includes groups 1 and 2, as well as helium (group 18).
- Elements in p-block have their last electron in the p-subshell. This includes groups 13 to 18.
- Elements in d-block have their last electron in the d-subshell. This includes groups 3 to 12.
- Elements in f-block have their last electron in the f-subshell. This includes the lanthanides and actinides.
4. Determine the group of the element by looking at its atomic number or electron configuration. The group number is equal to the number of valence electrons in the element's outermost energy level.
Conclusion:
By understanding the periodic table's structure, we can use an element's atomic number to find its period, block, and group. The atomic number helps determine the period, while the type of subshell containing the last electron determines the block. The group number is based on the element's valence electrons.
How to find the period ,block and group of an element by it's atomic n...
For period ther is a trick...After electric configuration... count the number of shells...and...No..of shells is equal to Period....And...for group...Use their outermost valence electrons... If the valence electrons will be...1,2.3...then..the group will be same...and after that...add 10 on each...for example....Carbon.. there outermost.. elctron is 4 ..so add 10 ..and.Ur answer will be 14...
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