Radioactive Tracers Are Useful in Studying Very Low Concentrations of Chemical

question 56

Multiple Choice

Radioactive tracers are useful in studying very low concentrations of chemical species. A chemist has a sample of HgI₂ in which part of the iodine is the radioactive nuclide of mass 131, so that the count rate is 5.0  10¹¹ counts per minute per mole of I. The solid mercuric iodide is placed in water and allowed to come to equilibrium. Then 100 mL of the solution is withdrawn, and its radioactivity is measured and found to give 22 counts per minute. What is the molar concentration of iodide ion in the solution?

• A) 1.1  10^-11
• B) 1.1  10^-9
• C) 1.1  10^-10
• D) 4.4  10^-10
• E) 4.4  10^-11

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Definitions:

Control Theory

Holds that the rewards of deviance and crime are ample. Therefore, nearly everyone would engage in deviance and crime if they could get away with it. The degree to which people are prevented from violating norms and laws accounts for variations in the level of deviance and crime.

Healthy Social Change

Positive transformation within society that leads to improvements in health, well-being, equity, and social justice.

Durkheim

Refers to Émile Durkheim, a French sociologist, who is a founding figure in the field of sociology and is best known for his theory on social facts and his studies on the division of labor, suicide, and religion.

Tolerance

The willingness to accept feelings, habits, or beliefs that are different from one's own; openness to diversity.