NCERT Activity 5.6Class 10 Science Explanation with conclusion

If you are looking for NCERT Science Class 10 Chapter 5 Activity solutions, then you are at the right place. In this post, you will find NCERT Activity 5.6 Class 10 Science Explanation with conclusion.

NCERT Activity 5.6 Class 10 Science Explanation with conclusion

You are suggested to study NCERT activity 5.6 class 10 science explanation with conclusion so that you can attempt questions based on the activity 5.6 class 10 science.

Class 10 Science Chapter 5 Periodic Classification of Elements

 Activity 5.6 Class 10 Science

·     How do you calculate the valency of an element from its electronic configuration?

·     What is the valency of magnesium with atomic number 12 and sulphur with atomic number 16?

·   Similarly, find out the valencies of the first twenty elements.

·     How does the valency vary in the period going from left to right?

·     How does the valency vary in going down a group?

Discussion 

·     Valency is defined as the combining capacity of the atom of an element with the atoms of other elements in order to acquire 8 electrons.

For elements of groups 1, 2, 13, and 14, the valency is equal to the number of valence electrons and for elements of groups 15-18, the valency is equal to 8.

·     Electronic configuration of Mg is 12

K            L             M

2             8             2            

Therefore, the number of electrons in the valence shell (M=shell) = 2.

As the element belongs to group 2, therefore, its valency is equal to the number of electrons in the valency shell = 2.

The electronic configuration of sulphur is 16

   K            L             M

   2             8             6                  

Therefore, the number of electrons in the valence shell = 6.

As the element belong  to group 16, it needs 2 electrons to complete its octet therefore, its valency = 8 - 6 = 2.

·   This is to be noted that the number of valence electrons, i.e., 2 – 2 = 0. The valency of the first 20 elements is shown below: 

·  Since the elements present in a period do not have the same number of valence electrons, they do not show the same valency. In a period, the valency first increases from 1 to 4 and then decreases from 4 to zero. 

· In a group, all the elements present have the same electronic configuration of their atoms. Therefore, all the elements in a group have the same valency. For example, the valency of all the elements of group I is 1, that of group 13 is 3, and so on. 

     

    Related Topics for You

1. Next Activity - Activity 5.7 Class 10 Science

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3. NCERT Solutions of Class 10 Science Chapter 5

4. MCQ Questions of chapter 5

5. Solutions of Class 10 Science all chapters

5. Extra Questions of Chapter 5