Scientists can determine the age of ancient objects by the method of radiocarbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope of carbon, 14C, with a half-life of about 5,730 years. Vegetation absorbs carbon dioxide through the atmosphere, and animal life assimilates 14C through food chains. When a plant or animal dies

A certain drug has a half-life in the body of 7.5 h. What should the interval between doses be, if the concentration of drug in the body should not fall below 25.% of its initial concentration? Round your answer to 2 significant digits.

The amount of 14C in an old, isolated sample of vegetation is 0.770 that expected from a present day sample with an equivalent carbon content. Calculate the age of the old sample in years.

Hi, I need help with this step-by-step, please. Thank you.    Even more interesting is how the researchers determined the age of the sharks. Normally, youcould look at the decay of carbon-14 in the bone of an animal to determine its age. By comparingthe current amount of carbon-14 in the bone to the amount of carbon-14 that was in the boneinitially, you can determine how much time has passed (the age of the animal). This doesn’twork with Greenland sharks, though! Greenland sharks don’t have bones. They just havecartilage. Researchers determined, however, that the carbon-14 in certain proteins in the eye lensof the sharks could be dated because those proteins are set from the time that the shark is bornand are never replaced (most proteins in living organisms are constantly being broken down andreplaced, but not these proteins in the eye lens of the Greenland shark!).[Here’s the problem to solve and the information you need to solve it.] Let’s assume thatresearchers find a new Greenland…

An archaeologist finds some ancient jewelry made from bone. The jewelry has a carbon mass of 484 g (HINT: Assume all the carbon is 12C and determine the number of atoms, 12C has a molar mass of 12 g/mol) and careful measurements show that the remaining 14c has a current decay rate of 11 decays/s. Determine the age of the bone (and presumably the jewelry). The ratio of 14C to 12c when the animal died was 1.25x10-12 & the half-life of 14c is 5730 y. Additionally, 1 mol = 6.022x1023 365.25 days, & 1 day = 24 h. particles, 1 y = age of bone =

The hat life for the radioactive decay of rubidium-87 to strontium-87 is 4.88 x10^10 years. Suppose nudear chemical analysis shows that there is 0.688 mmol of strontium-87 for every 1.000 mmol of rubidium-X7 in a certain sample of rock. Calculate the age of the rock. Round your answer to 2 significant digits.

The half-life of carbon-14, an isotope used in archaeological dating, is 5730 years. What percentage of 14 6C remains in a sample estimated to be 17,000 years old?

The half life for the radioactive decay of potassium-40 to argon-40 is 1.26 x 10 years. Suppose nuclear chemical analysis shows that there is 0.280 mmol of argon-40 for every 1.000 mmol of potassium-40 in a certain sample of rock. Calculate the age of the rock. Round your answer to 2 significant digits. |years

Which of the following would have a density of 0.0866 g/L at 7.0°C and 0.987 atm? SO 2 H 2 Rn He Ar