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2 years ago

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Q 32.35: The isotope 235U decays by alpha emission with a half-life of 7.0 x 108 y. It also decays (rarely) by spontaneous fissi

on, and if the alpha decay did not occur, its half-life due to spontaneous fission alone would be 3.0 x 1017 y. At what rate do spontaneous fission decays occur in 1.0 g of 235U

1 answer:

Julli [10]2 years ago

5 0

Answer:

rate of fission =5.89*10^3 1\Year

Explanation:

we know that

rate of fission is given as $rate of fission = \frac{0.69}{(T_{1/2})_{fission}} *\frac{ Mass* Avogardo\ number}{Molar\ mass}$

$(T_{1/2})_{fission} = 3*10^{17} y$

mass = 1.0 g

avogardo number = 6.02*10^23

molar mass of isotopes 235U =235

Putting all value to get rate of emission

rate of fission $= \frac{0.69}{3*10^{17}} *\frac{1.0*6.02*10^{23}}{235}$

rate of fission =5.89*10^3 1\Year

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<em><u>The knowable variables are </u></em>

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$t_{1}=1.3 s$

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Since we know the velocity in two points and the time the car takes to pass the traffic signs

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