A chemist wishing to do an experiment requiring 47-Ca2+ (half-life = 4.5 days) needs 5.0 μg of the nuclide. What mass of 47-CaCO3 must be ordered if it takes 24 h for delivery from the supplier? Assume that the atomic mass of 47-Ca is 47.0 u.

Mass = μg

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Answer:

5.8μg

Explanation:

According to the rate or decay law:

N/N₀ = exp(-λt)------------------------------- (1)

Where N = Current quantity,  μg

            N₀ = Original quantity, μg

             λ= Decay constant day⁻¹

              t =  time in days

Since the half life is 4.5 days, we can calculate the  λ from (1) by  substituting N/N₀ = 0.5

0.5 = exp (-4.5λ)

ln 0.5  = -4.5λ

-0.6931 = -4.5λ

λ =   -0.6931 /-4.5

  =0.1540 day⁻¹

Substituting into (1)  we have :

N/N₀ = exp(-0.154t)----------------------------- (2)

To receive 5.0 μg of the nuclide with a delivery time of 24 hours or 1 day:

N = 5.0 μg

N₀ = Unknown

t = 1 day

Substituting into (2) we have

[5/N₀]   = exp (-0.154 x 1)

    5/N₀        = 0.8572

N₀  =  5/0.8572

     =    5.8329μg

    ≈     5.8μg

The Chemist must order 5.8μg  of 47-CaCO3

"When The Chemist must order 5.8μg of 47-CaCO3 = 5.8μg To understand more information check below".

What is Decay law?

Now, According to the rate of decay law:

Then, N/N₀ is = [tex]exp(-\lambda)[/tex]-------------------eq. (1)

Where N is = Current quantity, μg

N₀ is = Original quantity, μg

Then, λ= Decay constant day⁻¹

After that, t is = the time days

When the half-life is 4.5 days, Then, we can compute the λ from (1) by substituting N/N₀ = 0.5

Then, 0.5 is = exp (-4.5λ)

After that, ln 0.5 = -4.5λ

Now, -0.6931 is = -4.5λ

Then, λ = -0.6931 /-4.5

After that, =0.1540 days⁻¹

Now, Then Substituting into (1) we have :

Then, N/N₀ is =[tex]exp(-0.154t)[/tex]--------------eq. (2)

After that, To receive 5.0 μg of the nuclide with a delivery time of 24 hours or 1 day:

N is = 5.0 μg

Then, N₀ is = Unknown

After that, t is = 1 day

Then, Substituting into (2) we have

After that,[tex][5/N₀] = exp (-0.154 x 1)[/tex]

Now, 5/N₀ = 0.8572

Then, N₀ = 5/0.8572

Now, = 5.8329μg

Hence,  ≈ 5.8μg

Thus, The Chemist must order 5.8μg of [tex]47-CaCO3[/tex]

Find more information about Decay law here:

https://brainly.com/question/9902363