Question

any two
S OT the apo
bove compou
32. Three elements X, Y, and Z with their atomic numbers are given below:
3M
Element
Atomic Number
X Х
16
Y
18
Z
19
Examine the above data and answer the following questions:
A) How many valence electrons are present in Y? What is its valency?
B) Write the position of X and Z in the Modern Periodic Table.
C) Write the molecular formula formed between X and Z​

Answer 1

Answer:

Explanation:

Correct option is

C

8, 8, 8

M shell means it is third shell ⇒n=3

For element X: atomic number = 18

thus its electronic configuration: 1s  

2

2s  

2

2p  

6

3s  

2

3p  

6

 

Electrons in M shell=2+6=8

For element Y: atomic number = 19

thus its electronic configuration: 1s  

2

2s  

2

2p  

6

3s  

2

3p  

6

4s  

1

 

Electrons in M shell=2+6=8

For element Z: atomic number = 20

thus its electronic configuration: 1s  

2

2s  

2

2p  

6

3s  

2

3p  

6

4s  

2

 

Electrons in M shell=2+6=8

thus in element X,Y,Z the number of electrons in M shell is 8,8,8 respectively.