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Shkiper50 [21]
3 years ago
15

If a sample has 25% parent and 75% daughter, how many halflifes have gone by?

Chemistry
1 answer:
Anit [1.1K]3 years ago
6 0

Answer:

Two half lives.

Explanation:

It is known that the decay of isotopes and radioactive material obeys first order kinetics.

Also, it is clear that in first order decay the half-life time is independent of the initial concentration.

That means for a sample 100% to decay to 50 % it will take one half-life, and to decay the remaining 50% to 25% it will take another half-life.

So, for a sample has 25% parent and 75% daughter it will have two half-lives.

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Xg ---------- 100%
X = (254×100)/0,39
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If a solution containing 51.429 g of mercury(ii) perchlorate is allowed to react completely with a solution containing 16.642 g
OLga [1]
Hg(No3)2  +NaSO4   --->2NaNO3  +  HgSO4(s)
calculate  the moles  of   each  reactant
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mass  of  HgSO4=moles  x  molar   mass  of  HgSo4=  0.117 g x  303.6g/mol=  35.5212  grams

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4 years ago
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alexandr1967 [171]

Answer:

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Explanation:

I hope this helps!

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