Question

What is the formula of the hydride formed by krypton?

Answer 1

Krypton does not form covalent compounds with hydrogen.

Explanation:

However, at 25 °C and pressures greater than 5.3 GPa (52 000 atm) it forms a "van der Waals compound" called krypton hydride with the formula `"Kr"("H"_2)_4`.

The hydrogen atoms exist as hydrogen molecules that are attracted to the krypton atoms only by van der Waals forces.

The `"Kr"` atoms arrange themselves into octahedra (green), and the octahedra are arranged in a face centred structure.

The hydrogen molecules (gray) are randomly oriented in four different types of "holes" between the octahedra.