$-16-$

$8823-6114$

$5.$ Beryllium is a low$-$density metal that is used in specialized lightweight alloys.

$($a$)$ Beryllium has a crystalline structure.

$($i$)$ State the technique that would be used to determine the crystal structure of beryllium.

$1$

$($ii$)$ Outline the electrostatic attraction in the beryllium crystal structure.

$[1]$

$($b$)$ The production of beryllium is illustrated in the diagram.

$($i$)$ Outline why molten $BeC{l}_2$ is considered an electrolyte.

$[1]$

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