63. The uncoiling of deoxyribonucleic acid (DNA) is a first- order reaction. Its activation energy is 420 kJ. At 37°C, the rate constant is 4.90 × 10-4 min-1. (a) What is the half-life of the uncoiling at 37°C (nor- mal body temperature)?

Q: If a sample of 131La goes from 450 picocuries to 100 picocuries in 185 minutes, what is its…

A:

Q: Technetium-99m, a metastable state of technetium-99 commonly used in nuclear medicine, has a…

A:

Q: Bandages can be sterilized by exposure to gamma radiation from cobalt-60, which has ahalf-life of…

A: Given: The mass of the sample is 5.27 Y. The half-life of cobalt-60 is 5.27 y.

Q: The half-life of Phosphorus-32 is 14.3 days. If you start with 100 grams of it, how long will it…

A: Half life of a first order reaction is given by , t1/2=0.693k Write the expression for first order…

Q: 19. The half-life of carbon-14 is 5730 years. A plant fell into a tar pit 18,400 years ago before…

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Q: Substance D initially weights 56 grams. After 6 minutes, it was observed that its mass decreased by…

A:

Q: 120 mg sample of technium 99m is used for a diagnostic test. if a technium 99m has a half-life of…

A: Given- Initial mass = 120 mg Half life = 6.0 hrs To find- milligrams of the technetium 99M sample…

Q: Radioactive Parent Stable Daughter Product Half-life Potassium-40 Argon-40 1.25 billion…

A:

Q: What is the half-life of the bizarre isotope Toddium - 419 (it is a makeup element) if after 4.00…

A: Time period, t = 4.00 weeks Initial amount, [A]o =950.0 g Final amount, [A] = 29.6875 g Calculation…

Q: Technetium-99m, an important radionuclide in medicine, has a half-life of 6.0 hours. What percentage…

A: Formula for radioactive decay is given as,

Q: The half-life of tritium is 12.5 years. How much will remain after exactly 100 years if you start…

A:

Q: -) The half-life of lodine-131 is 8.0252 days and the decay is first order. If 14.4 grams of 1-131…

A: Half life of iodine-131 (t1/2) = 8.0252 daysInitial amount of I-131 = [I-131]0 = 14.4 gamount of…

Q: Technetium-99m, an important radionuclide in medicine, has a half-life of 6.0 hours. What percentage…

A: Half life of technetium - 99 is = 6 hours.  Let Take a sample of technetium - 99 having number of…

Q: If you start with a 13.16 g sample of Pt197which has a half-life of 19.89 hours, what is the mass of…

A:

Q: A 120-mg sample of technetium-99m is used for a diagnostic test. If technetium-99m has a half-life…

A: Rate of a reaction determines the speed with which a reaction proceeds. First order reaction is a…

Q: Americium-241 is widely used in smoke detectors. Calculate the amount of americium-241 consumed in a…

A: The objective of the question is to calculate the amount of Americium-241 consumed in a smoke…

Q: 3. An archeologist unearths a bone sample and wants to know the age of the initial amount of…

A: Given:  Present amount of bone = 49 %  Half life = 5730 years

Q: If 25.35 grams of radioactive waste reduces to 9.75 grams of radioactive waste after 1350 years,…

A: Given, time = 1350 years  Half life , t1/2 = ?

Q: 210Rn has a half-life of 2.4 hours. You have a sample that contains 24 g of 210Rn. How much 210Rn…

A: The relationship between the half-life, T1/2 and the decay constant is given by  or,  The…

Q: You are on a geology field trip to the La Brea Tar Pits, and you find a jaw bone from a…

A:

Q: 1. A lab tech prepares 50.0 mg of I-123 on Tuesday, how many mg will remain 39 hours later if the…

A:

Q: You have a sample of Bismuth-212 to prepare for an upcoming medical test.  This isotope has a…

A: The radioactivity follows first-order kinetics. The half-life relates to the rate constant, k for…

Q: Sodium-24 is used to treat leukemia and has a half-life of 15 hours. A patient was injected with a…

A: Radioactive disintegration  is very unstable nucleus loosing energy  and it follows first order

Q: 8. Strontium-90 has a half-life of 28.1 years. Starting with 2.08 mg of this isotope, what is the…

A: Radioactive decay follows first order kinetics. Using this we will calculate all parts of questions.

Q: The half-lives of different radioisotopes are given in the table. Radioisotope Half-life (min)…

A: Answer: Since, nuclear reactions are first order reactions, therefore to solve this question we will…

Q: The half-life of 9USr is 29 years. What fraction of the atoms in a sample of 0Sr would remain 175…

A: here we are required to find the fraction of sample of Sr that would remain after 175 years later

Q: A substance has a half-life of two days.  If 10 days have passed, how many half-lives has the…

A: Half life means the time in which amount of substance become half of its initial value

Q: Oxygen-15 is an isotope of oxygen that is used in the medical procedure called a PET scan. The…

A: Given that, the half-life of oxygen-15 is t1/2 = 2 min. A hospital needs 1 g of oxygen-15. The…

Q: How old is a bottle of wine if the tritium ( 3H) content is 25% that of a new wine? The half-life of…

A: step1: Radioactive decay:-The emission of energy in the form of ionizing radiation is known as…

Q: A to 240mg sample of technetium 99M is used for a diagnostic test. if Technetium -99m has a…

A:

Q: Gallium-67 is used medically in tumor-seeking agents. The half-life of gallium- 67 is 78.2 hours.…

A: Given   The half-life is 78.2 hours. The fall in activity of gallium-67 is 29.1 percent of its…

Q: Technetium-99m (the ‘m’ means a ‘metastable’ or moderately stable species) is generated in nuclear…

A: Use half life and date constant formula  Final mass= 125.95mg

Writing and Balancing Nuclear Equations

A nuclear equation is a symbolic representation of a nuclear reaction using certain symbols. It is studied in nuclear chemistry and nuclear physics.