Collagen is used to date artifacts. It has a rate constant = 1.20 x 10-4 /years. What is the half life of collagen?

A drug has an elimination half-life of 3 hours. (1) For a one-time dose of 16 mg that is completely absorbed into the body, how much is left in the body at the end of 6 hours? (2) Find the elimination constant for this drug. (3) If instead of a one time dose, 16 mg of this drug is administered every 6 hours. What is the amount of drug in the body immediately after the 5th dose?

the half-life of the antidepressant Prozac in an average man is 2 days. how long in days does it take for 95% of the original dose to be eliminated from a man's body?

The half-life of percocet in the human body is 4 hours. If someone currently has 12 mg of the drug in their body, how many milligrams were in the original dose, taken 12 hours ago?

4. Which statement is true about a reactant that appears in the balanced equation for a reaction but does not appear in the rate equation? (A) It is an inhibitor. (B) It is not part of the reaction. (C) Its concentration is too low to be important. (D) It takes part in the reaction after the rate- determining step.

Americium-241 is used in smoke detectors. It has a first order rate constant for radioactive decay of k= 1.6 x 10¹ yr. By contrast, phophorus-32, which is used for the analysis of metabolic pathways, has a rate constant for radioactive decay of k = 0.050 day-1 ▾ How much of a 2.50 mg sample of americium remains after 3 half-lives? Express your answer in milligrams to two significant figures. ▾ TTL = ▾ Part E Submit TIL = How much of a 1.51 mg sample of phophorus remains after 3 half-lives? Express your answer in milligrams to two significant figures. Templates Symbols Undo redo Peser keyboard shortcuts help Templates Symbols Undo redo es keyboard shortcuts Help n Submit Part F TTL= Request Answer How much of a 1.00 mg sample of americium remains after 4 days? Express your answer in milligrams to two significant figures. Part G Submit Request Answer Templates Symbols Undo redo Teset keyboard shortcuts Help n ** Previous Answers Request Answer How much of a 1.35 mg sample of phophorus…

The half life of caffeine in the human body is 6 hours. There is approximately 260 mg of caffeine in a Grande Starbucks coffee. If you drank the coffee at 9am, what time would it be when there is only 65 mg of caffeine left in your body?

2:43 1 4 7 +/- Question 2 of 13 lodine-123 is a radioactive isotope used to study thyroid gland functions. It decays in a first-order process with a half life of 13.1 h. You receive a 10.00 g sample for some of your experiments, but you have to work fast before it is all gone. Calculate the number of hours it will take for 8.50 g of your sample to decay. 2 5 8 3 60 9 O h Submit Tap here or pull up for additional resources XU x 100

Enzymes are remarkably efficient catalysts that can increase reaction rates by as many as 20 orders of magnitude.(a) How does an enzyme affect the transition state of a reac-tion, and how does this effect increase the reaction rate?(b) What characteristics of enzymes give them this tremendous effectiveness as catalysts?

. The half-life of thallium−201 is three days. What fraction of thallium−201 is still present in an individual after twelve days? (Report your answer in fraction format.)