Which of the following compounds would be properly classified as ionic? (You may select more than one compound.)
   (a)   NH4NO3
   (b)   HOCN
   (c)   NF3
   (d)   K2O
   (e)   MgCl2
   (f)   Li2
   (g)   SF4



Which of the following molecules would you expect to have a resultant dipole moment (μ)?

Select all that apply.

   (a)   AlCl3
   (b)   SCl4
   (c)   SnCl2
   (d)   OCSe
   (e)   ICl3
   (f)   XeF2
   (g)   SbI3


Which one of the following molecules has a permanent dipole moment?
   (a)   PH3
   (b)   SF6
   (c)   SO3
   (d)   XeF4
   (e)   CCl4

Which of the following compounds would be properly classified as ionic? (You may select more than one compound.)
(a) NH4NO3
(b) HOCN
(c) NF3
(d) K2O
(e) MgCl2
(f) Li2
(g) SF4

metals and non metals form ionic compounds .NH4+ is a cationic radical with positive charge so it also form ionic compounds
a) NH4NO3
(d) K2O
(e) MgCl2
(f) Li2 ( ionic attractions in Li+ and free  electrons )

Which of the following molecules would you expect to have a resultant dipole moment (μ)?

Select all that apply.

(a) AlCl3
(b) SCl4
(c) SnCl2
(d) OCSe
(e) ICl3
(f) XeF2
(g) SbI3

Check the symmetry of the molecules which you can easily predict after deciding about the shape of the molecule
Like AlCl3 is a trigonal planar and is symmetrical .Hence no dipole moment.
similarly try others

hich one of the following molecules has a permanent dipole moment?
(a) PH3
(b) SF6
(c) SO3
(d) XeF4
(e) CCl4
same here
check for the shape after making lewis diagram and than for the symmetry .
If it is symmetrical dioples will cancel out.Like SO3 has trigonal planar and has symmetry

(f) Li2 ? it exists or hypothetical or something ?

Ionic crystal or molecule of NaCl ,its dipole moment is Q1Q2/ r^2 ?
Every ionic crystal have covalent nature so all of them have dipole moments right?

Dipole Moment of any Ionic crystal always greater than a Covalent molecule ?

Li2 is a theoretical molecule .
NaCl is an ionic compound and not a molecule .
Ionic compounds have extremely high dipole moments because of complete charge transfer.