Concept explainers
The way the universe would have been different if the half-life of
Answer to Problem 16Q
If the half- life of
Explanation of Solution
Given:
The half- life of
Formula used:
The half- life equation,
Calculation:
Analyzing the two situations where the half-life of
For zero half- life,
This means
If
For
The final amount of particles is the same as the initial amount. The result implies that
Most of the elements having a similar number of protons and neutrons are stable especially if the number of protons is even.
An
In a core of a star with enough pressure and mass, two
On the other hand, if
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Chapter 19 Solutions
Universe: Stars And Galaxies
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- Can you guys answer so its easier to understand? The isotope cobalt-60 has a nuclear mass of 59.933820 u. Calculate the binding energy per nucleon of cobalt-60 using the following information. Mass of Proton: 1.007825 uMass of Neutron: 1.008665 u1 u = 931.5 MeVarrow_forwardPart 1: Carbon dating An archaeologist finds some ancient jewelry made from bone. The jewelry has a carbon mass of 387 g (HINT: Assume all the carbon is 12C and determine the number of atoms, 12C has a molar mass of 12 g/mol) and careful measurements show that the remaining 14C has a current decay rate of 20 decays/s. Determine the age of the bone (and presumably the jewelry). The ratio of 14C to 12C when the animal died was 1.25x10-12 & the half-life of 14C is 5730 y. Additionally, 1 mol = 6.022×1023 particles, 1 y = 365.25 days, & 1 day = 24 h. age of bone = Part 2: Rubidium-Strontium dating A geologist finds an old rock and wants to determine its age using rubidium-strontium dating. This is possible because 87Rb, which has a half-life of 4.75×1010 y, undergoes - decay and becomes 87Sr. The geologist determines that the ratio of 87 Sr to 87Rb is 0.033. Assuming there was no 87Sr in the rock when it was formed, determine the age of the rock. age of rock =arrow_forwardThe initial amount of carbon-14 is 100 g and the amount of carbon-14 dropped to 1 g after decay process. The half-life of carbon-14 is 5,730 y . Calculate the time taken to complete this decay process. (a) 3.8x10* y (b) 6.0x102 y (c) 4.0×10 y (d) 5.0x10' yarrow_forward
- The half-life of a certain radioactive material is 32 days. An initial amount of the material has a mass of 361 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 5 days. Round your answer to the nearest thousandth.arrow_forwardI asked the following question and was given the attached solution: Suppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 4 kg r = 0.0407 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3) I don't follow the work and I got the wrong answer, so please help and show your work as I do not follow along easily thanksarrow_forwardCalculate the energy released in the fusion reaction H+H He +n The atomic mass of H (tritium) is 3.018049 11. Express your answer in megaelectronvolts to three significant figures. IVE ΑΣΦ |Q|- MeVarrow_forward
- What is the percentage difference mass loss between a Helium nucleus and 4 protons? My math came out to 99% but I think I did something wrong (this assumes the mass for of 4 protons is 6.6792 x 10^-27kg and a the mass of a helium nucleus is 6.6892e x 10^-27kg (Units need to be in kilograms to use with e=mc^2)arrow_forwardSuppose that the universe were full of spherical objects, each of mass m and radius r . If the objects were distributed uniformly throughout the universe, what number density (#/m3) of spherical objects would be required to make the density equal to the critical density of our Universe? Values: m = 4 kg r = 0.0407 m Answer must be in scientific notation and include zero decimal places (1 sig fig --- e.g., 1234 should be written as 1*10^3)arrow_forwardIn a cyclotron facility, 106 atoms of F-18 were created. The half-life of F-18 is 110 minutes. After the target has sat and decayed for 220 minutes, how many F-18 atoms are left? 3.0 x 105 atoms 1.5 x 105 atoms 2.5 x 105 atoms 2.0 x 105 atomsarrow_forward
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