Arsenic poisoning is a serious problem in Bangladesh, China, and Chile, resulting from contaminated well water. When arsenic poisoning occurs, arsenic binds to proteins and eventually causes cellular damage. This leads to a variety of symptoms in humans including exhaustion, muscle weakness, organ failure, and cancer. Arsenic poisoning is commonly treated with a drug called dimercaprol (or BAL) that binds arsenic. This process sets up a competing equilibrium within the body. Once arsenic reacts to form a complex with BAL, it can be excreted from the body. How does excretion of the arsenic-BAL complex affect the equilibrium shown below? Arsenic-protein complex Arsenic + proteins + BAL Arsenic-BAL

Question

Arsenic poisoning is a serious problem in Bangladesh, China, and Chile, resulting from contaminated well water. When arsenic poisoning occurs, arsenic binds to proteins and eventually causes cellular damage. This leads to a variety of symptoms in humans including exhaustion, muscle weakness, organ failure, and cancer. Arsenic poisoning is commonly treated with a drug called dimercaprol (or BAL) that binds arsenic. This process sets up a competing equilibrium within the body. Once arsenic reacts to form a complex with BAL, it can be excreted from the body. How does excretion of the arsenic-BAL complex affect the equilibrium shown below? Arsenic-protein complex  Arsenic + proteins + BAL  Arsenic-BAL

Quizplus · Accepted Answer

Excretion of the arsenic-BAL complex removes arsenic from the system, which shifts the equilibrium to the right in order to maintain equilibrium. As more arsenic-BAL complex is excreted, the reaction will continue to favor the formation of more of the complex to maintain equilibrium. This means that less of the arsenic-protein complex will be formed, as there is less arsenic available to bind to proteins. Therefore, choice D is the correct answer.

Arsenic Poisoning Is a Serious Problem in Bangladesh, China, and Chile