The minimum photonic energy required to create an electron-positron pair is 1.022 MeV. This energy is the equivalent of the rest masses of the pair of particles created. There is a bit more to this, as conservation of momentum must be observed. Pair production will occur, when it occurs, in the vicinity of an atomic nucleus when a high energy gamma ray zips in. The nucleus provides some "help" to "balance the equations" that describe the event, and that atomic nucleus will allow symmetry to be preserved. Specifically, that atomic nucleus acts in the conservation of momentum. That's why pair production won't occur as gamma rays are flying through the vacuum of space; there are (virtually) no atoms out there to facilitate the event. It may sound complex, but it's not all that difficult to get a handle on the phenomenon. A link is provided to our friends at Wikipedia. Knowledge there is free, and pair production isn't all that tough to understand. The article is brief and readable, and the complex equations that might have been posted are absent. Check it out.
The energy needed for ionization is called ionization energy. It is the minimum amount of energy required to remove an electron from an atom or molecule in its gaseous state.
true activation energy is the minimum amount of energy needed to start a chemical reaction
The minimum amount of energy required for a reaction to occur is called the activation energy. This energy is needed to break the bonds in the reactant molecules and initiate the chemical reaction. Once the activation energy is overcome, the reaction can proceed on its own.
The minimum amount of energy needed to start a reaction is called the activation energy. It is required to break the bonds in reactant molecules and initiate the process of forming new bonds in the products. This energy barrier must be overcome for a chemical reaction to occur.
Chemists call the energy needed to get a reaction started the activation energy. This energy is required to break the bonds of the reactant molecules before they can form new bonds and produce products.
Pair production can only occur if the energy of the photon is bigger than the rest mass (E0 = m0*c^2) of electron and positron, because this is the energy needed to create these particle (conservation of energy). Excess energy will be kinetic energy of the electron and positron. Rest mass of electron and positron is 0.511 MeV each, so 1.022 MeV in total.
The minimum amount of unstable atoms needed to produce an uncontrolled chain reaction is called?
The activation energy.
Energy.
Water.
The minimum amount of unstable atoms needed to produce an uncontrolled chain reaction is called critical mass.
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The energy needed for ionization is called ionization energy. It is the minimum amount of energy required to remove an electron from an atom or molecule in its gaseous state.
true activation energy is the minimum amount of energy needed to start a chemical reaction
The minimum amount of energy required for a reaction to occur is called the activation energy. This energy is needed to break the bonds in the reactant molecules and initiate the chemical reaction. Once the activation energy is overcome, the reaction can proceed on its own.
It is same as the animals.It produce energy needed.
Of course they have. They are needed to produce energy