Chapter 4: Structure of Atom- Exercise- 50

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Chapter 4: Structure of Atom

Class: IX

Exercise number 50

 

Question 1

Write the distribution of electrons in carbon and sodium atoms?

Answer 1

The total number of electrons in a carbon atom is 6. The distribution of electrons in carbon atom

is given by:

First orbit or K-shell = 2 electrons

Second orbit or L-shell = 4 electrons

Or,

we can write the distribution of electrons in a carbon atom as 2, 4.

The total number of electrons in a sodium atom is 11. The distribution of electrons in sodium atom

is given by:

First orbit or K-shell = 2 electrons

Second orbit or L-shell = 8 electrons

Third orbit or M-shell = 1 electron

Or,

we can write distribution of electrons in a sodium atom as 2, 8, 1.

Question 2

If K and L shells of an atom are full, then what would be the total number of electrons in the atom?

Answer 2

K and L-shells of an atom can occupy a maximum of  2 and 8 electrons respectively. Therefore, if  an atoms K and L-shells are full, then it contain a total of  10 (2 in K shell +  8 in L shell)electrons.