Arsenic exhibits dose-dependent toxicity in humans and has been shown to cause lung and skin cancer...

   

Transcribed Image Text:

Arsenic exhibits dose-dependent toxicity in humans and has been shown to cause lung and skin cancer with prolonged and chronic exposure. Arsenic salts are used to aid in the electrodeposition of gold and the long-term exposure to arsenic by metal galvanizing factory workers was determined by neutron activation analysis. Workers from various parts of the factory submitted hair and nail clipping samples for inclusion in the study. A reference standard of hair containing 0.65ug/g arsenic was irradiated along with the samples. After a 12 hour neutron irradiation followed by a decay time of 3 halflives, the samples were taken for gamma spectroscopy using an HPGe detector (25% detection efficiency at the 559keV photopeak of As-76; 0.45 absolute intensity). Q7A. If 100mg of the standard resulted in 9200 CPM and 150mg of Sample X resulted in 10250 CPM, what was the arsenic content of Sample X? Q7b. Using the activation of the reference standard, calculate the thermal neutron flux of the neutron source. (mass of standard, m=100mg; radiative thermal neutron capture cross-section of As-75, 0=4.5b; As-76 half-life, t1/2=1.08 days=26 hours) Arsenic exhibits dose-dependent toxicity in humans and has been shown to cause lung and skin cancer with prolonged and chronic exposure. Arsenic salts are used to aid in the electrodeposition of gold and the long-term exposure to arsenic by metal galvanizing factory workers was determined by neutron activation analysis. Workers from various parts of the factory submitted hair and nail clipping samples for inclusion in the study. A reference standard of hair containing 0.65ug/g arsenic was irradiated along with the samples. After a 12 hour neutron irradiation followed by a decay time of 3 halflives, the samples were taken for gamma spectroscopy using an HPGe detector (25% detection efficiency at the 559keV photopeak of As-76; 0.45 absolute intensity). Q7A. If 100mg of the standard resulted in 9200 CPM and 150mg of Sample X resulted in 10250 CPM, what was the arsenic content of Sample X? Q7b. Using the activation of the reference standard, calculate the thermal neutron flux of the neutron source. (mass of standard, m=100mg; radiative thermal neutron capture cross-section of As-75, 0=4.5b; As-76 half-life, t1/2=1.08 days=26 hours)

Answer rating: 100% (QA)

Q7A To determine the arsenic content of Sample X we need to use the information provided about the counts per minute CPM for the standard and Sample X Given CPM of the standard 100mg 9200 CPM CPM of S... View the full answer