The alloy used in the contruction of aircrafts is :

• Mg-Al

• Mg-Mn

• Mg-Zn

• Mg-Sn

Which of the following structure is similar to graphite? 

• BN

• B

• B₄
  

• B₄
  

293.

The basic structural unit of silicates is 

• SiO^-

• SiO₂^4-

• SiO₃^2-

• SiO₃^2-

Which of the following is electron deficient

• (CH₃)₂

• (SiH₃)₂

• (BH₃)₂

• (BH₃)₂

Name the type of the structure of silicates in which one oxygen atom of [SiO₄]^4- is shared?

• Sheet silicate

• Pyrosilicate

• Three-dimensional silicate

• Three-dimensional silicate

The tendency of BF₃, BCl₃ and BBr₃ to behave as Lewis acid decreases in the sequence

• BCl₃ > BF₃ > BBr₃

• BBr₃ > BCl₂ > BF₃

• BBr₃ > BF₃ > BCl₃

• BBr₃ > BF₃ > BCl₃

The correct regarding the electronegativity of hybrid orbitals of carbon is: 

• sp> sp²<sp³

• sp> sp² > sp³

• sp< sp² > sp³

• sp< sp² > sp³

The correct order of atomic radii in group 13 elements is

• B < Al < In < Ga < Tl

• B < Al < Ga < In < Tl

• B < Ga < Al < In < Tl

• B < Ga < Al < Tl < In

In which of the following, the oxidation number of oxygen has been arranged in increasing order?

• BaO₂ < KO₂ < O₃ < OF₂

• OF₂ < KO₂ < BaO₂ <O₃

• BaO₂ < O₃ < OF₂ < KO₂

• KO₂ < OF₂ < O₃ < BaO₂

The magnitude of screening effect depends upon the number of

• inner electrons

• outer electrons

• bond order

• Both (a) and (b)