Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH, CsH, the correct order of increasing ionic character is

1.  LiH > NaH > CsH > KH > RbH

2.  LiH < NaH < KH < RbH < CsH

3.  RbH > CsH > NaH > KH > LiH

4.  KH < NaH < RbH < LiH < CsH

Hint: Down the group ionic character of metal hydride increases.

 
Metal hydrides are ionic, covalent or molecular in nature. Ionic character increases as the size of the atom increases or the
 
electronegativity of the atom decreases. The correct order of increasing ionic character is
 
LiH < NaH < KH < RbH < CsH