0.139 moles of plutonium are present in a sample containing 8.4 x 10²² atoms of Pt.
The number of moles of a substance can be calculated using the following expression:
no of moles = no of molecules ÷ 6.02 × 10²³
According to this question, 8.4 × 10²² atoms of plutonium are present in the molecule of plutonium.
no of moles = 8.4 × 10²² = 6.02 × 10²³
no of moles = 1.39 × 10-¹
no of moles = 0.139moles
Therefore, 0.139 moles of plutonium are present in a sample containing 8.4 x 10²² atoms of Pt.
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