if the half life of uranium 235 is 700 million years and you have 64 atoms of it, how many 700 million year units of time will pass before 1 atom of uranium 235 is left?

A robot spacecraft returned samples from the planetesimal 98765 ALEKS, located in the outer Solar System. Mass-spectroscopic analysis produced the following data on the isotopes of tin in these samples: isotope 118 "Sn 120 Sn Use these measurements to complete the entry for tin in the Periodic Table that would be used on 98765 ALEKS. Be sure your answers have the correct number of significant digits. Caution: your correct answer will have the same format but not necessarily the same numbers as the entry for tin in the Periodic Table we use here on Earth. 0 Sn mass relative (amu) abundance 117.9 54.% 0 119.9 Continue 46.% X S evee muuraw Hill LLC. All Rights Reserved. Submit Assignment Terms of Use | Privacy Center Accessibility

The abundance of 40K is 0.012% of total natural potassium. The human body is 0.25% potassium by mass. The half-life of 40K is 1.25 x 109 years.  What is the mass of potassium in a 70 kg human adult?

Carbon 14, with a half-life of 5700 years, is used to estimate the age of organic materials. What fraction of the original amount ofcarbon 14 would an object have if it were 2000 years old?

If a radioactive isotope has a half-life of 3 minutes, how much of the initial sample will be left after 7 minutes?

At the centers of some stars, oxygen-17 can undergo a fusion reaction with a proton (a hydrogen-1 nucleus) to produce two different nuclei. One of the products is an alpha particle (a helium-4 nucleus). What is the other? Write down the reaction equation for this transformation.

A radioactive substance is known to have a half-life of 78 years. Calculate the number of years it would take for this substance to decrease to 10% its original amount.

If we start with 6.4*10^12 atoms of a radioactive material with a half life of 1.2 days, how many atoms remain after 6 days?

A scientist discovers a new isotope, exponentialitium. The scientist sets aside 150 grams of exponentialitium. After 3 years, the scientist notices there is only 135 grams of exponentialitium left.  What is the half-life of this new isotope? Round your answer to four decimal places.

Assume you found a radioactive isotope that has a 1 million year half-life in an "old" bone. If you were to measure a 20% "parent" to 80% "daughter" ratio, how old is the bone? How would a bone twice as big change the count rate and the half-life?