Answer is: ammonia has a higher boiling point because it has stronger intermolecular forces.
Intermolecular forces<span> are the forces between </span><span>molecules. The stronger are intermolecular forces, the higher is boiling point of compound, because more energy is needed to break interaction between molecules.
</span>There are several types of intermolecular forces: hydrogen bonding, i<span>on-induced dipole forces, ion-dipole forces andvan der Waals forces.</span>
<span>There are a number of ways
to express concentration of a solution. This includes molarity. Molarity is
expressed as the number of moles of solute per volume of the solution.
Calculations are as follows:
Molarity of NO3 ion = 32.0 g Mg(NO3)2 ( 1 mol / 148.3 g ) ( 2 mol NO3 / 1 mol Mg(NO3)2) / .425 L
MOlarity of NO3 ion = 1.02 M </span><span>
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