The Half-Life of Cesium-137 Is 30 Years

question 25

Multiple Choice

The half-life of cesium-137 is 30 years.Suppose we have a 170-mg sample.How much of the sample remains after 140 years?

Understand the mechanisms and preferred positions for electrophilic aromatic substitution in pyridine.

Predict the major products of organic reactions involving pyridine and other nitrogen-containing compounds.

Identify appropriate reagents and conditions for specific organic transformations.

Explain the influence of substituents on the reactivity of pyridine towards electrophilic and nucleophilic substitution.

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