K+ is an electrolyte required by the human body and found in many foods as well as salt su...

K+ is an electrolyte required by the human body and found in many foods as well as salt substitutes. One of the isotopes of potassium is potassium-40, which has a natural abundance of 0.012% and a half-life of 1.30 × 109 y. The isotope potassium-40 decays to calcium-40 or to argon-40. A typical activity for potassium-40 is 7.0 μCi per gram.

Potassium chloride is used as a salt substitute.

a. Write a balanced nuclear equation for each type of decay.

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b. Identify the particle emitted for each type of decay.

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c. How many K+ ions are in 3.5 oz of KCl?

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d. What is the activity of 25 g of KCl in becquerels?