A 53.8-mg sample of sodium perchlorate contains radioactive chlorine-36 (whose atomic mass is 36.0 amu). If 29.6% of the chlorine atoms in the sample are chlorine-36 and the remainder are naturally occurring nonradioactive chlorine atoms, how many disintegrations per second are produced by this sample? The half-life of chlorine-36 is 3.0 * 10⁵ yr.

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Convert the mass of the sodium perchlorate sample from milligrams to grams by dividing by 1000.

Calculate the molar mass of sodium perchlorate (NaClO₄) using the atomic masses of sodium (Na), chlorine (Cl), and oxygen (O).

Determine the number of moles of sodium perchlorate in the sample by dividing the mass of the sample in grams by the molar mass of sodium perchlorate.

Calculate the total number of chlorine atoms in the sample by multiplying the number of moles of sodium perchlorate by Avogadro's number (6.022 x 10²³ atoms/mol).

Find the number of chlorine-36 atoms by multiplying the total number of chlorine atoms by the percentage of chlorine-36 (29.6%).

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