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hichkok12 [17]
4 years ago
14

A certain radioactive element has a half-life of one hour. if you start with 1.0 gram of the element at noon, how much of the ra

dioactive element will be left at 2 p.m.? 0.50 grams 0.25 grams 0.125 grams 0.0 grams
Chemistry
2 answers:
kvv77 [185]4 years ago
7 0

Answer:

The radioactive element will be left at 2 p.m. will be 0.25 g.

Explanation:

Half life of the radioactive element =t_{\frac{1}{2}}=1 hour

Initial concentration of the radioactive element = N_o=1.0 g

Time elapsed = 12:00 pm to 2:00 pm = 2 hours

Concentration of radioactive element left = N

\lambda =\frac{0.693}{t_{\frac{1}{2}}}=\frac{0.693}{1 hr}=0.693 hr^{-1}

\log N=\log N_o-\frac{\lambda t}{2.303}

Putting the given values in the above equation we get:

N = 0.25 gram

The radioactive element will be left at 2 p.m. will be 0.25 g.

skelet666 [1.2K]4 years ago
3 0
Answer: 0.25 g
I just took this test and that was the answer to it. 

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