Why does oxygen have a lower melting point than nitrogen?

TL;DR: Nitrogen has higher electron density than oxygen meaning you have to remove more energy to overcome the repulsive forces. From the atomic perspective, different phases are when the molecules overcome repulsive forces.

Why is the melting point of oxygen much lower than sulphur?

There is large difference between the melting and boiling points of oxygen and sulphur. Due to much larger molecular size of S8 molecule as compared to O2 molecule, the van der Waals forces of attraction are much stronger in S8 molecules than in O2 molecules.

How is oxygen different below its melting point and above it?

This means at temperatures below that point, oxygen is a solid or a liquid, and at temperatures above that point, oxygen is a gas. So at -183 degrees Celsius, oxygen is a liquid.

Why oxygen has low melting and boiling point?

The van der Waals forces of attraction between O2 molecules are relatively weak owing to their much smaller size. The large van der Waals attractive forces in the S8 molecules are due to large molecular size. Therefore oxygen has low m.p. and b.p. as compared to sulphur.

Why does melting point decrease from Nitrogen to fluorine?

In the case of Nitrogen, which exists as a diatomic molecule – this shrinking in size is less than that for oxygen and fluorine. the melting point is determined by the intermolecular interactions as well as the geometry of molecules. greater the number of bonds to break, higher is the melting point.

Why does O2 have a lower boiling point than F2?

Answer: 1. Dipoles in London forces are present in all compounds, can occur between atoms or molecules, are due to electron movement, are transient in nature (dipole-dipole are more permanent). O2 would have a lower boiling point, because F2 have stronger London attractions due to molecule’s size.

Why does sulphur have a higher boiling point than oxygen?

Hence larger atoms or molecules made of larger atoms (here say Sulphur) have strongest induced dipole-induced dipole attractions (strong London dispersion forces). Due to which Sulphur having stronger intermolecular forces has higher melting point and boiling point than oxygen with weaker intermolecular forces.

Why does sulphur show more Catenation than oxygen?

Although sulphur and oxygen belong to the same group, sulphur still has a greater tendency to catenate than oxygen. This is because the oxygen belongs to the second period. So, the filling takes place in 2p orbital while the sulphur belonging to the third period has filling in 3p orbitals.

How do the boiling point and melting point differ?

This is when they become a liquid. So the melting point is the temperature at which molecules in a solid can move past each other and form a liquid. The boiling point is the temperature at which the gas from the liquid is pushing the air with the same force the air is pushing back.

Why is the melting point and freezing point the same?

Upon cooling, the particles in a liquid lose energy, stop moving about and settle into a stable arrangement, forming a solid. Freezing occurs at the same temperature as melting, hence, the melting point and freezing point of a substance are the same temperature.

Does oxygen have a low melting point?

The normal melting point of oxygen is -218°C; its normal boiling point is -189°C. Oxygen is a gas at room temperature. If both the normal melting point and the normal boiling point are above room temperature, the substance is a solid. Sodium chloride melts at 801°C and boils at 1413°C.

Why is the boiling point of sulfur higher than oxygen?

A molecule of sulphur is made of Packard ring of eight atoms joined together by strong covalent bonds while a molecule of oxygen has weak van der waal forces between the molecules hence higher boiling point in sulphur than oxygen.