A certain drug has a half-life in the body of 3.5 h. Suppose a patient takes one 300. mg pill at 7:00PM and another identical pill 45 min later. Calculate the amount of drug left in his body at 10:00PM. Be sure your answer has a unit symbol, if necessary, and round it to 3 significant digits. 559. mg 0 x10 X

The half life for the radioactive decay of potassium-40 to argon-40 is 1.26 × 10⁹ years. Suppose nuclear chemical analysis shows that there is 0.677 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 x10 X Ś

Radioisotope X has a half-life of 4.0 h. Based on the figure below, if the original sample of the radioisotope was 16.00 g, what percentage of the sample would be left after 12.0 hours?Radium-223 dichloride (also called Xofigo) with a half-life of 11.4 days has been approved by the FDA to treat metastatic prostate cancer: Indicate the number of half-lives that has elapsed for a sample 45.6 days after application.

The half life for the radioactive decay of carbon-14 to nitrogen-14 is 5.73x 10^3 years. Suppose nuclear chemical analysis shows that there is 0.888 mmol of nitrogen-14 for every 1.000 mmol of carbon-14 in a certain sample of rock. Calculate the age of the rock. Round your answer to 2 significant digits.

a) Chemical X has a half-life of 27 days. Based on this, if we have 3 liters of pure Chemical X today, how much pure Chemical X will we have in one week (i.e. seven days)? 10. b) By doing detailed regression analysis, the mad scientist Doctor Z has determined that his blob is growing exponentially with its weight, in kilograms, given by W(t) = 0.005e0.00023t where t is in seconds. How long will it take for the blob to weigh 100 kg (and thus be able to serve as an effective weapon against Doctor Z's archrival Professor U?)

What is a chain reaction and what causes it?

A certain drug has a half-life in the body of 5.5 h. What should the interval between doses be, if the concentration of drug in the body should not fall below 35.% of its initial concentration? Round your answer to 2 significant digits.

Lisinopril is an ACE inhibitor derived from the venom of a Brazilian pit viper frequently used in the treatment of hypertension. Because of Lisinopril's relatively long half life of 12 hours, patients need to take a dose just once per day. A patient takes his first dose, 20 mg, at 6 pm on Saturday. a) How many hours does it take for the amount of Lisinopril in the patient's body to decrease to 16 mg? Round to two decimal places. b) How many milligrams remain in the patient's body right before he takes his next 20 mg at 6 pm on Sunday? Round to two decimal places

Indium-116 is radioactive and has a half life of 14.10 seconds. How long would it take a sample to decay from 2.10 mg to 500. µg. Round your answer to 2 significant digits. S x10 X Ś

18. Why is the neutron to proton ratio so important? Scientists made up this concept because they wanted to create radiation. An atom's nucleus likes to have the same number of neutrons and protons, so knowing that ratio is important. It determines the stability of the nucleus based on the shielding effect of the neutrons. The neutron to proton ratio describes a radioactive element's half-life. hp esc @ # $ &. 1 2 4. W e r y tab 10