Question

& Why do you think more energy is required to separate two xenon atoms than is required to separate particles involved, are stronger than gravitational forces, which depend on the mass of the particles. two neon atoms? Remember that electrical forces, which depend on the number and charges of the 9. Why do you think that energy is required to separate two water molecules in an anti-parallel configuration, but in a parallel configuration, water molecules repel each other? (Remember that oxygen is more electronegative than hydrogen. This means that the oxygen in water is slightly negatively charged, and the hydrogen is slightly positively charged.)

Answer 1

8.) There are weak London Dispersion forces acting between the noble gas atoms. This is an instantaneous dipole-induced dipole interaction. Xenon(Xe) has large number of electrons and also larger in size than that of Neon(Ne). Because of that Xe atoms have greater tendency, to distort the outer-most electron cloud, i.e. to build instantaneous dipoles, compared to Ne atoms. So the attractive force is greater between Xe atoms than in Ne atoms. That's why, more energy is required to separate two Xe atoms than is required two Ne atoms.

9.) In parallel orientation water molecules repel each other due to the reinforcement of dipole moment along the same direction. But in case if anti-parallel orientation, the dipole moments tend to cancel each other, oppositely charged atoms come closer to each other, resulting in building net attraction between two molecules.

instantaneous dipole -induced dipale interaction. X6L SHS+ St H St H+ 05K HS* Net dipole moment acting on same direction. - repel each other dipole moments acting on opposite directions, => Attractive force developes betn turo molecules.

10.) In head to tail orientation water molecules form strong intermolecular H-bonding between them; and those H-bonds hold the water molecules more tightly. Therefore in this orientation water has much greater dissociation energy compared to the parallel and antiparallel oriented water.

I I interaction. O.--. I 20 H-bonding 0- Intermolecular --- o – I I

11.) The reason is the acting forces between the substance particles/molecules. If the kinetic motion between the molecules overcome the attractive forces that hold the molecules in a definite orientation, or, in lattice cells, then the substance moves freely and randomly and exists in gaseous state. For liquids and solids the attractive forces are far greater and the kinetic motion of the molecules can not overcome these forces to move freely.