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jarptica [38.1K]
3 years ago
6

Select the correct answer.

Chemistry
1 answer:
lidiya [134]3 years ago
8 0

Answer:

8.36 g

Explanation:

From;

0.693/t1/2 = 2.303/t log (No/N)

t1/2 = half life of potassium-40

t = age of the sample

No= initial amount of the sample

N= amount of the sample at time t

Substituting values;

0.693/1.3 × 10^9 = 2.303/2.6 × 10^9 log (No/2.10)

5.33 × 10^-10 = 8.86 × 10^-10 log (No/2.10)

5.33 × 10^-10/8.86 × 10^-10 = log (No/2.10)

0.6 = log (No/2.10)

Antilog (0.6) = (No/2.10)

No = 2.10 × Antilog (0.6)

No= 8.36 g

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<h3>Empirical formula </h3>

To calculate the empirical formula of a compound, the value of moles of each element is needed.

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As the value of the empirical formula must be an integer, simply multiply the two values ​​by a common factor:

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