I have a question about water/ice.?

Question

This has bothered me forever! How come when you melt most elements, such as iron, they go from solid, to malleable, to gooey and so on until it is completely liquid but when you melt ice, it goes from solid, to fully liquid?

I guess another way to state the question is why doesn't water change it's viscosity when it changes from a solid to a liquid?

Answer 1

metals have denser volumes . so metals take more time to melt and  to the form of full liquiddyy they need more time.

Answer 2

Good question.

I'm not a materials scientist but I think it is related to intermolecular attraction, namely van der Waals forces.

Water molecules are highly polar and once they receive sufficient kinetic energy to dissociate from each other (from solid to liquid) this strong polarity will cause them to repel each other overcome the molecular attractions (including hydrogen bonding). Also because water has a high heat of fusion, the molecules receive a large amount of energy in the water to ice phase change.

By contrast, iron is an amorphous solid composed of non-polar atoms which have no inherent force acting against the various van der Waals forces that tend to attract them. In this regard, non-tempered iron is more like a glass and it's viscosity alters proportional to temperature. As in the viscosity graph linked below, iron does become less viscous as its temperature rises.

I hope that gets you closer to an answer.

Answer 3

Many materials melt abruptly with little loss of rigidity beforehand (aluminum, water, salt), and many soften first (iron, wax, glass). It probably has to do with the size of the crystals. Crystal themselves are very rigid, but the bond between them can vary considerable with temperature. Large crystal solids retain more of the mechanical properties of the crystals themselves in their bulk properties.