After 5715 years (1 half life)
Mass remaining = 20.0/2 = 10.0 g
After 11430 years (2 half lives)
Mass remaining = 10.0/2 = 5.0 g
After 17145 years (3 half lives)
Mass remaining = 5.0/2 = 2.5 g
Typing The Answer Is Mandatory The half-life of carbon is 5700 years. A substance was found that originally contained 40 grams of carbon-14. It now contains 10 grams of carbon-14. Predict how old the substance is. Explain how you arrived at this prediction.
If a radioactive isotope has half-life h, then the number of atoms in a sample is given by a(t)=a-2-/h where ao gives the number of atoms in the sample at time 0. The radio active decay of carbon-14 leads to clever way of determining the age of fossils and remnants of plants and animals. When an organism dies, the radioactive carbon- 14 in it decays, with half of it gone in 5,730 years. a. Suppose a mummified cat has a...
14 C is a radioactive isotope of carbon, which decays with a const ant half-life of 5730 y. If a Megatherium (giant sloth) skull contains 0.011% of the 14 C it did when the animal was alive, how old is the tusk?
When a plant or an animal dies, its 14C content decreases with a half-life 5730 years. If an archeologist finds an ancient firepit containing partially consumed firewood and the 14C content of the wood is only 15% that of an equal carbon sample from a present-day tree, what is the age of the ancient site?
2. Half-life is the time required for half of an amount of a particular compound to degrade (see table below). The half-life of DDT in the soilis from 2 to 15 years, and the half-lite of DDT in an aquatic environment is 150 years. 1 half-life 2 half-lives 3 half-lives 4 half-lives 5 half-lives 50% degraded 75% degraded 88% degraded 94% degraded 97% degraded a. If the original concentration of DDT in the water is 2 ppm, how much DDT...
The carbon-14 to nitrogen-14 radiometric isotope decay series has a half-life of 5 730 years. If you find an ancient bone in Africa that has a ration of carbon-14 to nitrogen-14 of 1:15, how old is the bone?
Some fossil bones containing 1/32 of their original amount of carbon-14 are found. How many half-lives have passed? How old are the bones? (HINT: The half-life of carbon-14 is 5,730 years. If 1/8 of the original amount of carbon-14 was present, 1/8 = 1/23 or 1/(2x2x2), therefore 3 half-lives would have passed and therefore, the bones would be 5,730 years x 3 = 17,190 years old)
Carbon-14 is a radioisotope that is used for dating biological organisms. The half-life of C-14 is 5730 years. When a one-gram sample of carbon from fresh peat is measured for radioactivity, 900 beta decays are recorded every hour. A one-gram sample of carbon is obtained from a peat deposit and is measured for radioactivity. If 113 beta decays are observed every hour, how many half-lives of C-14 have passed since the deposit was formed? A. 1/8 B.3 C.113 D.8 Approximately...
The half-life for the radioactive decay of C-14 is 5730 years. If a sample of C-14 initially contains 1.6 mmol of C-14, how many millimoles will be left after 2250 years?
The half-life of carbon-14 is 5730 years. How long does it take for 3.6 grams of carbon-14 to be reduced to 1.3 grams of carbon-14 by radioactive decay? years (Do not round until the final answer. Then round to the nearest hundredth as needed.)