Question

Can someone help me with number 3 of my pchem homework?

Uranium-lead dating is an important technique for determining the age of rocks that formed from about million years to over 4.5 billion years ago with routine precisions in the 0.1-1 percent range (according to Wikipedia). Uranium-235 decays according to actinium series: 235U207 Pb+7a +4B with a rate constant of 0.00097626 mition years I.) Determine the order, rate law, and integrated rate law for this decay process. 2. Determine the half-life of 235U decay. Provide your answer in millions of years. 3.)What percentage of the original 25U would you expect to remain on earth considering that earth formed 4.543 x 10 years ago?

Answer 1

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