The average activity of air inside homes in the United States is about 1.5 pCi per...

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The average activity of air inside homes in the United States is about 1.5 pCi per liter. What is the average activity of a liter of air, in Bq? In decays per hour? SOLUTION SET UP We use the average value just cited, 1.5 pCi/L, along with the conversion factor 1 Ci = 3.7 x 1010 Bq. SOLVE Since 1 Bq = 1 decay/s, the number of decays in 1 hour is 1.5 pCi/L = (1.5 10-12 Ci/L) (3.7x101B = 0.056 Bq (0.056 decays/s) (3600 s/h) = 200 decays/h REFLECT A level of activity of air of 1.5 pCi/L represents, on average, the decay of one Rn nucleus every '18 s in each liter of air. If the basement of a medium-size house of 106 L, the total activity of the air in this basement is about 1.5 x 10-6Ci, or about 5 x 104 disintegrations per second. Part A - Practice Problem: If your lungs contain an average of 5.4 L of air, how many decays occur each minute? for Part A for Part A undo for Part A redo for Part A reset for Part A keyboard shortcuts for Part A help for Part A 1.62 Submit Previous Answers Request Answer Incorrect; Try Again; 2 attempts remaining The average activity of air inside homes in the United States is about 1.5 pCi per liter. What is the average activity of a liter of air, in Bq? In decays per hour? SOLUTION SET UP We use the average value just cited, 1.5 pCi/L, along with the conversion factor 1 Ci = 3.7 x 1010 Bq. SOLVE Since 1 Bq = 1 decay/s, the number of decays in 1 hour is 1.5 pCi/L = (1.5 10-12 Ci/L) (3.7x101B = 0.056 Bq (0.056 decays/s) (3600 s/h) = 200 decays/h REFLECT A level of activity of air of 1.5 pCi/L represents, on average, the decay of one Rn nucleus every '18 s in each liter of air. If the basement of a medium-size house of 106 L, the total activity of the air in this basement is about 1.5 x 10-6Ci, or about 5 x 104 disintegrations per second. Part A - Practice Problem: If your lungs contain an average of 5.4 L of air, how many decays occur each minute? for Part A for Part A undo for Part A redo for Part A reset for Part A keyboard shortcuts for Part A help for Part A 1.62 Submit Previous Answers Request Answer Incorrect; Try Again; 2 attempts remaining