contestada

A radioactive isotope has a half-life of 10 years. What fraction of the original mass will remain unchanged after 50 years

Respuesta :

The fraction is calculated like this:

[tex] \frac{1}{ {2}^{50 \div 10} } = \frac{1}{32} [/tex]

If you want an universal equation for all problems like this:

[tex] \frac{1}{ {2}^{time \div halflife} } [/tex]

The fraction of the original mass of the radioactive isotope with a half-life of 10 years that will remain after 50 years is 1/32.

We can find the fraction of the original mass with the exponential decay equation:

[tex] N(t) = N_{0}e^{-\lambda t} [/tex]  (1)

Where:

N(t): is the amount of radioactive isotope at time t

N₀: is the initial amount of radioactive isotope

λ: is the decay constant

t: is the time = 50 y

We can find the decay constant as follows:

[tex] \lambda = \frac{ln(2)}{t_{1/2}} [/tex]   (2)

Where:

[tex]t_{1/2}[/tex]: is the half-life of the isotope = 10 y

The decay constant is (eq 2):

[tex] \lambda = \frac{ln(2)}{t_{1/2}} = \frac{ln(2)}{10 y} = 0.069 y^{-1} [/tex]

Now, the fraction of the original amount is (eq 1):

[tex] \frac{N(t)}{N_{0}} = e^{-\lambda t} = e^{-0.069 y^{-1}*50 y} = 0.0317 [/tex]

Since we need to calculate the fraction of the original mass, after some algebraic operations we have:

[tex] \frac{N_{0}}{N(t)} = 32 [/tex]  

[tex] N(t) = \frac{1}{32}N_{0} [/tex]                          

Therefore, the fraction of the original mass that will remain is 1/32.

Find more here:

  • https://brainly.com/question/4318844?referrer=searchResults
  • https://brainly.com/question/14020364?referrer=searchResults

I hope it helps you!  

Ver imagen whitneytr12