The Isotopes occur In Nature In The Ratio 140 : 1. Assuming That At The Time Of Earth’s Formation They Were Present In Equal ratio, make An Estimation Of The Age Of The Earth. The Half-lives Of respectively.

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Question

The isotopes occur in nature in the ratio 140 : 1. Assuming that at the time of earth’s formation they were present in equal ratio, make an estimation of the age of the earth. The half-lives of respectively.

None of these

diffcult

Solution

Correct option is

Let the number of atoms of at present be N₁ and N₂respectively. From the formula , we have

Because N₀ is same for both (given)

Where T₁ and T₂ are half-lives of respectively. Putting the given values :

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