One of the amazing products that have been developed under Van Der Waals forces is the <span>suction cup</span> that is used as an ankle and is used by workers as a safety gear on cleaning or constructing high-rise buildings.
<span>Like geckos, they can scamper up walls, scuttle along ceilings and hang upside down on polished glass surfaces.</span>
Explanation:
To delineate the the nature of the bonds that would be formed between the two elements, let us first write the electronic configuration of the two species;
Be = 2, 2
F = 2, 7
Beryllium is a metal with two valence electrons whereas fluorine is a halogen with seven valence electrons.
When Be loses two electrons it becomes isoelectronic with He;
Be → Be²⁺ + 2e⁻
Also, when fluorine gains an electron, it becomes isoelectronic with Ne;
F + e⁻ → F⁻
This loss and gain of electrons between the two elements creates an electrostatic attraction them and they enter into an electrovalent bond.
Hence;
Be²⁺ + 2F⁻ → BeF₂
V1M1c1 = V2M2c2
29 x 0.26 x 1 = V2 x 0.4 x 2
V2 = 9.425