Chapter Assessment Answer Key Chemistry: Matter and Change T167 4 CHAPTER ASSESSMENT Date alpha radiation Dalton’s atomic theory radiation radioactivity Chapter Assessment particles involved in a reaction. Chemistry: Matter and Change • Chapter 4 nucleus. A nuclear equation shows the atomic number and mass number of the 19 Both concern changes in atoms. A nuclear reaction involves a change in an atom’s 15. nuclear reaction, nuclear equation atom. in the nucleus of a given atom.
Describe two recent discoveries of transuranic elements explaining how they were produced. Firstly what is a transuranic element? Transuranic elements are elements with an atomic number above that of uranium with atomic number Z= 92. All transuranic elements are radioactive. The process of changing one element into another is called transmutation.
INTRODUCTION TO NUCLEAR REACTION: The main features of nuclear reactions include radioactive decay, nuclear fission and nuclear fusion. Radioactive decay: Energy is released in a radioactive decay in the form of the kinetic energy of the particle emitted (α and β), the kinetic energy of the daughter nucleus and the energy of the gamma-ray photon that may accompany the decay. The energy involved may be calculated by finding the mass defect of the reaction. The energy released is the energy equivalent of the mass defect of the reaction. Nuclear fission: Nuclear fission is the process in which a large nucleus breaks into two smaller nuclei that are almost equal in mass.
Because its density is so high, neutrons spin in the same way that electrons do so must obey the Pauli Exclusion Principle. 6. A pulsar does not pulse, it emits beams of radiation that sweep around the sky as the neutron star rotates, and astronomers detect pulses when they sweep over the Earth. 11. Sometimes in binary systems, mass flows into a hot accretion disk around the neutron star and causes the emission of x rays.
David Kemp OCR Chemistry A Unit 1: F321 Atomic Structure (a) describe protons, neutrons and electrons in terms of relative charge and relative mass; Proton +1 1 Neutron 0 1 Electron -1 1/2000 Relative Charge Relative Mass (b) describe the distribution of mass and charge Within an atom; Positively charged Nucleus containing most of the mass, surrounded by atomic shells with orbiting electrons of negative charge and negligible mass. (c) describe the contribution of protons and neutrons to the nucleus of an atom, in terms of atomic (proton) number and mass (nucleon) number. The atomic number of the nucleus, also the proton number, shows the number of protons in the nucleus. It also defines the element. The number of neutrons added to the number of protons is the nucleon number or mass number.
This saying has been proved by Quantum Physics and the law of conservation of energy with scientific experiments and become a universal law. At that point we accept the law of cause and effect, but why we should believe the necessity of the first cause (an uncaused cause) instead of infinite regress concerning the cause of the universe? According to the principle of sufficient reason by Gottfried Leibniz, there must be a cause for everything that comes into existence; the whole universe is a vast, interlocking chain of things that come into existence, as they come into existence, each of these things must have a cause. If there is no first cause, we can only explain each particular thing in short run by tracking the preceding mover, but nothing is explained in long run, or ultimately. In that case the whole universe is unexplained, which have violated the principle of sufficient reason for everything.
By doing this it was creating huge amounts of Energy. Scientists soon realized that they could use this energy to create very powerful bombs. Scientists started working vastly to create an atomic bomb. In this process they found that a rare form of Uranium was needed to create explosive chain reactions. This uranium was Uranium 235.
Also, for every force, there is an equal and opposite force acting against it. With the exception of gravity, the electromagnetic force is the force responsible for practically all the encounters in daily life above the nuclear scale. Roughly speaking, all the forces involved in interactions between atoms can be explained by the electromagnetic force acting on the electrically charged atomic nuclei and electrons inside and around the atoms, together with how these particles carry momentum by their movement. This includes the forces we experience in pushing or pulling ordinary material objects, which come from the intermolecular forces between the individual molecules in our bodies and those in the objects. With the exception of gravity, electromagnetic phenomena as described by quantum electrodynamics account for almost all physical phenomena observable to the human senses, including light and other electromagnetic radiation, all of chemistry, most of mechanics (excepting gravitation), and, of course, magnetism and electricity.
Nuclear Power is produced by controlled (non-explosive) reactors. They convert the thermal energy released from nuclear fission. When uranium and plutonium are enriched, it undergoes nuclear fission. It releases kinetic energy and gamma radiation. This whole process is called a nuclear chain reaction.
“Nuclear fission is the process of breaking up atoms; the process will generate an enormous amount of energy in form of heat” (Nuclear Power and the Environment). The first man-made reactor was built in the USA in December 2, 1942 called-