If you have 1.0 mol of each of the following compounds, which will have the greatest
mass?
oh3po4
o ni3
o fecl3
okci

NI3 has the highest molar mass = 394.707 grams

Explanation:

1 mole of each substance contain mass which is equal to molar mass of the substance .

Molar mass is calculated in the same way the molecular mass is calculated.

The Molar mass id expressed in grams.

Molecular mass = Mass of the atom x the number of atoms

Atomic mass of H = 1.00 amu

O = 15.99 amu

P = 30.97 amu

= 3(Mass of H) + 1(Mass of P) + 4(Mass of O)

= 3(1)+ 1(30.97) + 4(15.99)

= 3 + 30.97 + 63.96

= 97.93 gram

= 1 (mass of N) + 3(mass of I)

= 1(14.0067)+3(126.9)

= 394.7067 grams

= 1(atomic mass of Fe) + 3(atomic mass of Cl)

= 1(55.845)+3(35.45)

=  55.845 + 106.35

= 162.195 grams

KCl = 1(mass of K) + 1(mass of Cl)

= 1(39.09) + 35.45

= 74.54 gram

Out of these NI3 has the highest molar mass = 394.707 grams

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.