If You Obtained a Sample of Rock from Venus and Determined

question 51

Multiple Choice

If you obtained a sample of rock from Venus and determined the abundances of uranium (²³⁸U) and lead (²⁰⁷Pb) in it, and found that for every one uranium atom there were three lead atoms, then what would the age of this rock be? Note that this form of uranium decays to this form of lead with a half-life of 700 million years. For simplicity, you can assume that there was no lead in the rock when it originally formed.

• A) 1.4 billion years
• B) 2.8 billion years
• C) 4.0 million years
• D) 10.5 billion years
• E) 3.6 billion years

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Definitions:

Simplify

The process of altering an expression into its most basic or concise form, without changing its value.

Combine

To bring two or more elements together to form a single entity or result.

Simplify

Simplifying a mathematical expression or equation involves executing operations and merging similar terms to present it in its most basic form.

Combine

To merge or bring together two or more elements to form a single entity or total.