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The notation for the nuclide 13755Cs gives information about*
Which statement about one atom of an element identifies the element?*
Which quantity represents the number of protons in an atom?*
All phosphorus atoms have the same*
The numbers of protons and neutrons in each of four different atoms are shown in the table below.
Which two atoms represent isotopes of the same element?*
The nuclides I-131 and I-133 are classified as*
What is the charge of the nucleus of a copper atom?*
The three nuclides, U-233, U-235, and U-238, are isotopes of uranium because they have the same number of protons per atom and*
What is the charge of the nucleus of an oxygen atom?*
Base your answers to questions 10 on the information below.
The element boron, a trace element in Earth’s crust, is found in foods produced from plants. Boron has only two naturally occurring stable isotopes, boron-10 and boron-11.
Write an isotopic notation of the heavier isotope of the element boron. Your response must include the atomic number, the mass number, and the symbol of this isotope.*
Base your answers to questions 11 on the information below and on your knowledge of chemistry.
Iodine has many isotopes, but only iodine-127 is stable and is found in nature. One radioactive iodine isotope, I-108, decays by alpha particle emission. Iodine-131 is also radioactive and has many important medical uses.
Determine the number of neutrons in an atom of I-127.*
Base your answers to questions 12 on the information below and on your knowledge of chemistry.
A breeder reactor is one type of nuclear reactor. In a breeder reactor, uranium-238 is transformed in a series of nuclear reactions into plutonium-239.
The plutonium-239 can undergo fission as shown in the equation below. The X represents a missing product in the equation.
Determine the number of neutrons in an atom of the uranium isotope used in the breeder reactor.*
Base your answers to questions 13 on the information below and on your knowledge of chemistry.
Elements with an atomic number greater than 92 can be artificially produced in nuclear reactions by bombarding a naturally occurring nuclide with a different nuclide. One of these elements is roentgenium, Rg. The equation below represents a nuclear reaction that produces Rg-272.
State the location and the total charge of the protons in a Ni-64 atom.*
Base your answers to questions 14 on the information below and on your knowledge of chemistry.
The radioisotope Mo-99 naturally decays to produce the metastable isotope Tc-99m, which is used in medical diagnosis. A doctor can obtain images of organs and bones by injecting a patient with a solution of Tc-99m. The half-life of the metastable Tc-99m is six hours.
State both the number of protons and the number of neutrons in a Tc-99 nuclide.*
Base your answers to questions 15 on the information below and on your knowledge of chemistry.
The diagram below shows the first three steps in the uranium-238 radioactive decay series.
The decay mode for the first and third steps is shown above the arrows. The decay mode for the second step is not shown in the diagram. Thorium-234 has a half-life of 24.10 days.
Explain, in terms of neutrons and protons, why U-238 and U-234 are different isotopes of uranium.*
