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Svet_ta [14]
3 years ago
5

A certain radioactive isotope placed near a Geiger counter registers 160 counts per second. 32 hours later, the counter register

s 10 counts per second. What is the half-life of the isotope?
A. 8 hours

B. 16 hours

C. 24 hours

D. 32 hours

E. none of the above
Chemistry
2 answers:
stealth61 [152]3 years ago
7 0
I believe that the answer for this question would be option A. 8 HOURS. Based on the given scenario above about a certain radioactive isotope placed near a Geiger counter, the half-life <span>of the isotope 32 hours later would be 8 hours. Hope this is the answer that you are looking for. </span>
aev [14]3 years ago
7 0

Answer:

half life is 8.00 hours.

Explanation:

The radioactive disintegration follows first order kinetics.

The integrated rate law for first order kinetics is:

ln(\frac{[A_{0} ]}{[A_{t}]})=kt

Where

A0 = initial Geiger counter

At = final Geiger counter

t = time

k = rate constant

Let us calculate rate constant from the equation

ln(\frac{[160]}{[10]})=kX32

k = 0.0866 / hour

the relation between half life and rate constant for first order reaction is:

k =0.693 / half life

half life =0.693 /k = 0.693 / 0.0866 = 8.00 hours

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ddd [48]

Answer:

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Explanation:

Sodium chloride is a binary salt, very easy to dissolve in water, it is also called the famous table salt, since it can be ingested in food even though it is not so recommended against high blood pressure conditions.

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Gnoma [55]
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7 0
3 years ago
For the following reaction, the equilibrium constant Kc is 2.0 at a certain temperature. The reaction is endothermic. What do yo
jeyben [28]

Answer:

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Explanation:

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7 0
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Sphinxa [80]

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4 0
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Stells [14]
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δ<span>E = δq + δw</span>

where δ<span>E is the i change in internal energy, </span>

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δE = δq - p δ<span>V </span>
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4 0
3 years ago
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