Interpretation:
The concentration of calcium ions in the given sample of seawater is to be determined.
Concept Introduction:
For radioactive elements, the number of disintegrations per second occurring in them is defined as their activity. Mathematically, it is represented as follows:
The activity is known to be proportional to the number of radioactive nuclei,
Here,
To calculate the change in the number of nuclei per second:
The half-life for a first-order reaction is given as:
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Chemistry: The Molecular Nature of Matter
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