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LenKa [72]
3 years ago
8

the half life of I -137 is 8.07 days. if 24 grams are left after 40.35 days, how many grams were in the original sample?

Chemistry
1 answer:
Ray Of Light [21]3 years ago
4 0

Answer:

768g

Explanation:

We can use to formula N(A) = N_0(\frac{1}{2})^\frac{t}{t_{1/2}} . Here, N(A) is the final amount. N0 is the initial amount. t is the time elapsed, and t_{1/2} is the half life. Plugging in, we get the answer above.

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According to law of definite proportion, for a compound, elements always combine in fixed ratio by mass.

The formula of compound remains the same, let it be a_{x}b_{y} where, a and b are two different elements.

Since, the ratio of mass remains the same , calculate the ratio of masses of element a and b in both cases

\frac{a}{b}=\frac{15}{35}=\frac{10}{y}

rearranging,

y=\frac{10\times 35}{15}=23.3

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How many atoms are in NH4Cl.
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What are the concentrations of Cu2+, NH3, and Cu(NH3)42+ at equilibrium when 18.8 g of Cu(NO3)2 is added to 1.0 L of a 0.800 M s
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Explanation:

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8 0
3 years ago
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