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3 years ago

If a radioisotope has a half-life of 4 years, how much remains of a starting amount of 40 grams after 16 years have passed?

Chemistry

1 answer:

Gwar [14]3 years ago

5 0

Answer:

only 2.5 grams will be present after 16 years have passed

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What is the mass of KOH found in a 785 mL of a 1.43 M solution of KOH

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Molarity is defined as the ratio of number of moles to the volume of solution in litres.

The mathematical expression is given as:

$Molarity = \frac{Number of moles}{volume of solution in litres}$

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As, 1 mL = 0.001 L

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= 1.12255 mole

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3 years ago

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The third option is correct.

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