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The half-life of a chemical occurs every 8 years. If you end up with 1.93 grams, how much did you start with 30 years ago?

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Final answer:

To determine the initial amount of a chemical given its half-life of 8 years and remaining amount of 1.93 grams after 30 years, use the formula N = N_0 (1/2)^(t/T) and rearrange to solve for N_0. Plug in the given values to find the initial quantity.

Step-by-step explanation:

The question involves calculating the initial quantity of a chemical based on its half-life and the amount present after a certain period. The half-life is the time it takes for half of a substance to decay or reduce to half its original amount. To find out how much of a chemical you started with 30 years ago, given its half-life is every 8 years and the remaining amount is 1.93 grams, you can use the formula for exponential decay:

N = N0 (1/2)(t/T)

Where:

  • N is the final amount of the substance
  • N0 is the initial amount of the substance
  • t is the time that has passed
  • T is the half-life of the substance

Rearranging the formula to solve for N0, we get:

N0 = N / (1/2)(t/T)

Substituting the given values gives us:

N0 = 1.93 grams / (1/2)(30/8)

Calculating this out, we would find the initial amount of the chemical from 30 years ago.

User Rafael Companhoni
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