Answer:
Yes, it is reasonable to neglect it.
Explanation:
Hello,
In this case, a single molecule of oxygen weights 32 g (diatomic oxygen) thus, the mass of kilograms is (consider Avogadro's number):

After that, we compute the potential energy 1.00 m above the reference point:

Then, we compute the average kinetic energy at the specified temperature:

Whereas
stands for the Avogadro's number for which we have:

In such a way, since the average kinetic energy energy is about 12000 times higher than the potential energy, it turns out reasonable to neglect the potential energy.
Regards.
Answer:
Ice is water in solid phase, in this phase, the particles are very close together and relatively in fixed positions.
As the temperature starts to increase (thermal energy), also does the kinetic energy of the particles (so we have a change from thermal energy to kinetic energy), so they start to move "more", and the position of the particles starts to be less "fixed". There is a point where the particles have enough energy, and this point is where the phase of the water changes from solid to liquid phase (the fusion point). After this point the water can not hold his shape, and takes the shape of the container where it is.
Kinetic energy is the energy for a catapult.