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Eva8 [605]
3 years ago
9

A radioactive isotope has a half-life of 10 minutes.

Chemistry
1 answer:
stellarik [79]3 years ago
4 0

Answer: The time for activity to fell from 800 counts per second to 200 counts per second is 20 minutes

Explanation:

Expression for rate law for first order kinetics is given by:

t=\frac{2.303}{k}\log\frac{a}{a-x}

where,

k = rate constant

t = age of sample

a = let initial amount of the reactant

a - x = amount left after decay process  

a) for finding the rate constant:

Half life is the amount of time taken by a radioactive material to decay to half of its original value.

t_{\frac{1}{2}}=\frac{0.693}{k}

k=\frac{0.693}{10min}=0.0693min^{-1}

b) for activity to fell from 800 counts per second to 200 counts per second.

t=\frac{2.303}{0.0693}\log\frac{800}{200}

t=20minutes

The time for activity to fell from 800 counts per second to 200 counts per second is 20 minutes

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Select the more electronegative element in each pair.a.Cl or Fb.Se or Oc.N or Asd.Na or Mg
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The answer to your question is below

Explanation:

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Process

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3 years ago
If 3.6 g of aluminum completely reacts, how much Al2O3 (in grams) can be produced
marissa [1.9K]

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Let's balance it

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3.6 g of AL will give ?

cross multiply

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read more: brainly.com/question/23982245?referrer=searchResults

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