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Question
An element `""_ZS^A` decays to `""_85R^222` after emitting 2 α particles and 1 β particle.
Find the atomic number and atomic mass of the element S.
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Solution
`""_ZS^A -> ""_85R^222 + 2(""_2^4He) + 1 ""_"-1"^0e`
A = 222 + 2(4) + 0
∴ A = 230
Z = 85 + 2(2) + (-1)
∴ Z = 88
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