2 years ago

PLEASE HELP!

Chemistry

2 answers:

fgiga [73]2 years ago

5 0

150/30 = 5
HF1 20/2 = 10
HF2 10/2 = 5
HF3 5/2 = 2.5
HF4 2.5/2 = 1.25
HF5 1.25/2 = 0.625
Answer: 0.63g

NikAS [45]2 years ago

4 0

Answer: 0,63 g

Explanation: During 150 days 5 decays happen. You can write a set

of masses : 20 g ⇒ 10 g after first decay, then 5 g , 2.5 g , 1,25 g

and after fifth decay 0.63 g

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The frequency is $f = 2,01 * 10^{15} \ Hz$

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