Foil (metal)
A foil is a very thin sheet of metal, usually made by hammering or rolling. Foils are most easily made with malleable metals, such as aluminium, copper, tin, and gold. Foils usually bend under their own weight and can be torn easily. The more malleable a metal, the thinner foil can be made with it. For example, aluminium foil is usually about 1/1000 inch (0.03 mm), whereas gold (more malleable than aluminium) can be made into foil only a few atoms thick, called gold leaf. Extremely thin foil is called metal leaf. Leaf tears very easily and must be picked up with special brushes.
Group 12 element
Unhexquadium should be a soft metal like mercury, and metallic unhexquadium should have a high melting point as it is predicted to bond covalently. It is also expected to be a soft Lewis acid and have Ahrlands softness parameter close to 4 eV. It should also have some similarities to oganesson as well as to the other group 12 elements. Unhexquadium should be at most moderately reactive, having a first ionization energy that should be around 685 kJ/mol, comparable to that of molybdenum. Due to the lanthanide, actinide, and superactinide contractions, unhexquadium should have a metallic radius of only 158 pm, very close to that of the much lighter magnesium, despite its being expected to have an atomic weight of around 474 u, about 19.5 times as much as that of magnesium. This small radius and high weight cause it to be expected to have an extremely high density of around 46 g·cm, over twice that of osmium, currently the most dense element known, at 22.61 g·cm; unhexquadium should be the second most dense element in the first 9 periods of the periodic table, with only its neighbour unhextrium (element 163) being more dense (at 47 g·cm). Metallic unhexquadium should be quite stable, as the 8s and 8p electrons are very deeply buried in the electron core and only the 7d electrons are available for bonding. Metallic unhexquadium should have a very large cohesive energy due to its covalent bonds, most probably resulting in a high melting point.