Why is the diatomic molecule H2 more stable than two separate hydrogen atoms?

Answer 1

There are three sets of interactions in this system: The 4th explains: Why? # Repulsion between the two electrons (one interaction of this type) # Repulsion between the two nuclei (one interaction of this type) # Attractions between each electron and nucleus (four separate interactions of this type # Therefore a single hydrogen atom is less stable and requires less energy to break down.

Answer 2

It completes the octet rule, or in other words the valence shell is filled. Once hydrogen bonds with hydrogen it shares the two electrons and is stable like He. It requires less energy, and is therefore more stable, to bond.

Answer 3

H2 is more stable than 2H. That is, when two hydrogen atoms bond together the energy of the resulting hydrogen molecule (H2) is lower than the sum of the energies of the two free atoms (2H). This can be intuitively understood by thinking about the valence shells for these two examples. A valence shell is the outermost shell of electrons in an atom. Atoms "want" to have a full valence shell. Most shells are full with 8 electrons. The first shell will be full with 2 electrons. A single, neutral hydrogen atom has one electron in its valence shell. To fill the valence shell, one hydrogen can bond to another hydrogen. The two hydrogen atoms can share their electrons, thus each hydrogen atom will have a full valence shell.

But this explanation is only a way to intuitively understand why H2 is more stable than 2H. The truth is that any stable molecule will have a lower energy than the sum of its individual atoms. Energy is always released when chemical bonds are formed, and it always requires energy to break a chemical bond. This idea may sound counter-intuitive to many people. It is a common misunderstanding that the opposite is true; that by breaking chemical bonds energy is released and energy is required to form chemical bonds. Of course, an entire chemical reaction might require energy to occur (endothermic) or energy could be released over an entire chemical reaction (exothermic) but the individual bonds that are broken will always require energy while the bonds formed will always release energy.

Answer 4

The diatomic molecule H2 is more stable than two separate hydrogen atoms because when they bond to form H2, they share electrons, which results in a lower overall energy state. This bonding allows for a more stable arrangement of the atoms, with a lower potential energy compared to the separate atoms.

Answer 5

Because helium has completely filled orbitals, hydrogen doesnot.

Answer 6

Because contain two hydrogen atoms.