The nuclear equation below represents the alpha decay of 222/86 Rn --> 4/2 He + X What is the mass number of the element represented by X?

The mass number of X is 218.

Explanation:

Alpha decay : When a larger nuclei decays into smaller nuclei by releasing alpha particle. In this process, the mass number and atomic number is reduced by 4 and 2 units respectively.

General representation of an element is given as:  

where,

Z represents Atomic number

A represents Mass number

X represents the symbol of an element

General representation of alpha decay :

8 carbon atoms forming single bonds with 18 hydrogen atoms; a triple bond exists between the third and fourth carbon atom from the right

explanation:

yes

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