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In an ore containing uranium, the ratio ...

In an ore containing uranium, the ratio of `""^(238)U` to `""^(206)Pb` nuclei is 3. Calculate the age of the ore assuming that all the lead present in the ore is the final stable product of `""^(238)U`. Take half-life of `""^(238)U` to be `4.5xx10^(9)` years.

Text Solution

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Using N = `N_(0)e^(-lamdat)`, we get
`3=4e^(-lamdat)or4/3=e^(-lamdat)`
or `l n4-l n3=lamdat`
or `t=(l n4-l n3)/lamda=(l n4-l n3)/0.6931T`
= `(1.38629-1.09861)/0.6931xx4.5xx10^(9)`yr.
= `1.868xx10^(9)` yr.
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