It seems that mercury is one of those elements that’s hard to get a grasp on. It displays a liquid facade while actually being a metal. So what happens when you try to treat mercury like a liquid and soak it up with a sponge?
Would the sponge absorb it or not?
If your answer’s NO, then you guess it right! You might think it’s MAGIC but sorry it’s NOT!
The point is that, according to Quora, whether some liquid wets a solid, it depends on both the liquid’s property, as well as the solid’s property. In the case of water wetting sponge, it works because the sponge is made of hydrophilic (i.e. wets water) materials, if you use a sponge that is hydrophobic (i.e. does not wet water), then the sponge will no longer absorb the water. There are such sponges that are designed to absorb oil, oil and water usually behaves very differently when it comes to wetting behavior.
Another way to think about this is cohesion and adhesion, it actually uses the example of water and mercury to demonstrate the difference in cohesive and adhesive forces. Again, it’s always about the comparison between cohesion (affinity to itself) vs adhesion (affinity to another substance), it is never only about the liquid itself.
Granted, mercury has very very high surface energy, so it is extremely hard to find a solid has enough affinity to mercury molecules in order to wet it. But that is completely different than impossibility, as Quora User suggested,
This is why mercury won’t soak into anything, it can’t. No sponge could ever soak it up. “
In the field of materials science, we have been pushing the boundary of limitations in many aspects, such as melting point, strength, toughness, and many others. New material comes out everyday, there might already be some material out there that can wet mercury, for example, some sort of solid form mercury alloy with high mercury content, so the surface property is a lot like liquid mercury (“like attracks like”).