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Serhud [2]
3 years ago
10

The Half-Life of Pa-234 is 6.75 hours. How much (what fraction) of a sample of this isotope remains after 20.25 hours?

Chemistry
1 answer:
Grace [21]3 years ago
6 0
So in one hour half the amount remains (that's what half life means). In two hours 1/4 (or half of half) would remain and in three hours 1/8 would remain.
So the answer is 1/8
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Kepler and Newton studied the movement of planets. Kepler studied the speed of the planets while Newton studied the forces that
nasty-shy [4]
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4 0
3 years ago
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Red light has a wavelength of about 6.5 x 10-7m. Find its frequency. Show all work.
ozzi
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c = v x f

We know the wavelength of the an red light which is 6.5 x 10^-7 m. Now, we solve for the wavelength of the unknown wave to see the relation between the two waves.

2.998 X 10^8 = 5.3 X 10^15 X v
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3 0
3 years ago
Time that is measured in definite periods such as minutes, day,and years is called
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Answer:

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2.absolute time

Explanation:

Time that is measured in definite periods such as minutes, days, and years is called

a. Relative time.

b. absolute time.

7 0
3 years ago
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