Nuclear energy is called the energy obtained by the transformation of atomic nuclei, so small and heavy clusters of particles inside the atom. Nuclear energy can be produced in two ways, by cleavage or synthesis of nuclei. Heavy nuclei of radioactive elements such as uranium or plutonium, can be split into two nuclei. By splitting are released from the nucleus of neutrons that collide with other nuclei causing them to split and subsequent emission of neutrons. This is called a chain reaction. The condition calls self-sustaining nuclear reaction is slowing down neutrons. For this purpose, a special substance, called moderator. The neutrons collide with the molecules of the moderator precipitate heating speed while the moderator. The resulting heat heats the water so that a couple who drives a turbine generating electricity. Another way of producing nuclear energy is nuclear fusion, in which nuclei combine to light elements. So far, fusion, however, failed to carry out so that it can be applied to the economy as a source of energy.
Density is a physical property. It's measured and doesn't change the object chemically.
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Answer:
Adding a catalyst - More collisions every second and more collisions with enough energy to break bonds.
Increase in pressure - more collisions every second
Increase in temperature - more collisions every second with enough energy to break bonds
Explanation:
According to the collision theory, chemical reaction occurs as a result of collision between reacting particles. Only particles that possess energy above the activation energy of the reaction can collide and result in product formation. Collision of particles having energy less than the activation energy merely result in elastic collisions.
Adding a catalyst lowers the activation energy of the reaction. If the activation energy is lowered, more reactants collide and more of those collisions now have enough energy to break bonds.
When the temperature is increased, the particles become more energetic hence more collisions with energy to break bonds occur.
Increase in pressure brings the reactant particles into close proximity hence more collisions occur.