Chart:

Group, Bond length, Bond strength, H-X-H Bond Angle
NH3: 1.000, 391, 107
PH3: 1.412, 322, 93.5
AsH3: 1.510, 247, 92
SbH3: 1.688, 247, 92

What physical states do these molecules exist at room temperature? Gas

Briefly explain the observed trend in bond length.

Briefly explain the observed trend in bond strength.

Briefly explain the observed bond angles.

I having difficulty with trends with these and intermolecular forces. Could you please explain?

1 answer

On a periodic table bond lengths increase from right to left then bond the periodic table. Since these elements(N,P,AS, and Sb) are all in the same group you can just go down. Than is why Sb is the highest.

The bond strength is dependent upon the bond length. The longer the bond the weaker it is. This is why Sb and As are the lowest.

As for the bond angles, it depends on the number of lone pairs around the central atom. Since all the elements have the same number of lone pairs focus on its electronegativity. The smaller the atom size the greater the electronegativity. The more electronegative the central atom is, the higher the bond angle.