A radioactive sample is monitored with a radiation detector to produce 6640 counts per minute. Twelve hours later, the detector reads 1310 counts per minute.
1)Calculate the decay constant of the sample. (Express your answer to two significant figures.) (in h^-)
2)Calculate the half-life of the sample. (Express your answer to two significant figures.) (h)
A radioactive sample is monitored with a radiation detector to produce 6640 counts per minute. Twelve...
A Geiger counter reading of a radioactive sample is initially 7020 counts per minute. The same sample gives a reading of 402 counts per minute 10.6 h later. What is the sample's half-life?
A wooden artifact from a Chinese temple has a "C activity of 31.6 counts per minute as compared with an activity of 58.2 counts per minute for a standard of zero age. Part A You may want to reference (Pages 913-916) Section 21.4 while completing this problem. From the half-life for 14 C decay, 5715 yr, determine the age of the artifact. Express your answer using two significant figures. TO ALQ O a ? Submit Previous Answers Request Answer X...
A sample is counted and found to have 952 counts per minute. Seven minutes later it is measured again and has a count of 148 counts per minute. A background measurement gave 6 counts per minute. What is the half-life of the sample?
A Geiger counter registers a count rate of 7,600 counts per minute from a sample of a radioisotope. Ten minutes later, the count rate is 1,900 counts per minute. What is the half-life of the radioisotope?
A Geier counter registers a count rate of 6,000 counts per minute from a sample of a radioisotope. Eighteen minutes later, the count rate is 1,500 counts per minute. What is the half-life of the radioisotope? ________ minutes
The half-life for the radioactive decay of C−14 is 5730 years. If a sample of C−14 initially contains 1.7 mmol of C−14, how many millimoles will be left after 2250 years? Express your answer using two significant figures.
A) A radioactive material produces 1220 decays per minute at one time, and 4.2 h later produces 150 decays per minute. What is its half-life? B) What fraction of a sample of 6832Ge, whose half-life is about 9 months, will remain after 3.5 yr ? C) What is the activity of a sample of 146C that contains 7.0×1020 nuclei? The half-life of 146C is 5700 years.
The half-life for the radioactive decay of U−238 is 4.5 billion years and is independent of initial concentration. a) How long will it take for 17 % of the U−238 atoms in a sample of U−238 to decay? Express your answer using two significant figures and in yrs b) If a sample of U−238 initially contained 1.8×1018 atoms and was formed 4.9 billion years ago, how many U−238 atoms does it contain today? Express your answer using two significant figures.
The half-life for the radioactive decay of U−238 is 4.5 billion years and is independent of initial concentration. Part A How long will it take for 14 % of the U−238 atoms in a sample of U−238 to decay? Express your answer using two significant figures. Part B If a sample of U−238 initially contained 1.4×1018 atoms and was formed 5.7 billion years ago, how many U−238 atoms does it contain today? Express your answer using two significant figures.
The half-life for the radioactive decay of U−238 is 4.5 billion years and is independent of initial concentration. Part A How long will it take for 20% of the U−238 atoms in a sample of U−238 to decay? Express your answer using two significant figures. Part B If a sample of U−238 initially contained 1.5×1018 atoms when the universe was formed 13.8 billion years ago, how many U−238 atoms will it contain today? Express your answer using two significant figures.