Question

Which of the following cannot be
prepared directly from its elements
(A) BeH2
(B) MgH
(C) CaH
(D) BaH​

Answer 1

ANSWER

The electronegativity  of Cs = 0.7 and F = 0.4

Percentage of ionic character =16(χ  

A

​  

−χ  

B

​  

)+3.5(χ  

A

​  

−χ  

B

​  

)  

2

 

Here χ  

A

​  

andχ  

B

​  

 are electronegativity's of two atoms A and B

Percentage of ionic character

=16(0.7−0.4)+3.5(0.7−04)  

2

 =16(0.3)+3.5(0.09)

=4.8+0.315

=5.115

Answer 2

Answer:

The answer is a option B