1 4 7 lodine-123 is a radioactive isotope used to study thyroid gland functions. It decays in a first-order process with a half life of 786 min. You receive a 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 90% of your sample to decay. +/- 2 LO 5 Question 16 of 20 8 J hrs 3 6 O Submit Tap here or pull up for additional resources X C x 100

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Radioactive decay of 212Bi is observed to be a first-order process with a half-life (t½) of 4.00 days.  It is noted that a 1.70 g sample of 212Bi decays over 12 days to leave only 0.213 g behind.  What is the rate constant (k) for this process?   a. 12.0 day–1   b. 0.250 day–1   c. 0.173 day–1   d. 5.77 day–1   e. none of these

Remaining Time: 2 hours, 22 minutes, 53 seconds. Question Completion Status: Below is the initial rate data from a few experiments on the reaction: A+B> Products. [A]; (M) Experiment # 11 12 3 The reaction is first order in A. The rate constant is thus: O 5.656 Ms-1 O 2.828 M-1-1 O 11.31 s-1 O 1.414 M-25-1 1.00 2.00 2.00 QUESTION 7 Consider the following reaction: O Equal to the rate of reaction. O Three times the rate of reaction O Twice the rate of reaction One third of the rate of reaction [B]; (M) 2 03(g) -> 3 O2(g) What is the rate of consumption of O3 compared to the rate of reaction? O Half of the rate of reaction. 1.00 .00 2.00 Click Save and Submit to save and submit. Click Save All Answers to save all answers. Rate; (M s-1) 1.414 2.828 11.31 İy S

If the reaction is first-order with a half-life of 3.0 minutes choose the correct pictures which represent the reaction mixture after  3.0 minutes and 6.0 minutes have elapsed

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1 4 7 +/- lodine-123 is a radioactive isotope used to study thyroid gland functions. It decays in a first-order process with a half life of 786 min. You receive a 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 95% of your sample to decay. 2 LO Question 16 of 20 5 8 hrs 3 6 9 0 Submit Tap here or pull up for additional resources X C x 100

The rate constant for the radioactive decay of 14C is 1.21 × 10-4 year-1. The products of the decay are nitrogen atoms and electrons (beta particles): 1N+e- k[1&C] rate = What is the instantaneous rate of production of N atoms in a sample with a carbon-14 content of 6.5 x 10- M?