Answer:
Photoelectric effect, pair production and Compton scattering
Explanation:
Gamma rays, having no charge, can be slowed slowly by ionization as a material passes through. They suffer other mechanisms that eventually make them disappear, transferring their energy, they can cross several centimeters of a solid, or hundreds of meters of air, without undergoing any process or affecting the material they cross. Then they suffer one of the three effects and deposit much of their energy there. The three mechanisms of interaction with matter are: the photoelectric effect, the Compton effect and the production of pairs.
The photoelectric effect is that the photon meets an electron in the material and transfers all its energy, disappearing the original photon. The secondary electron acquires all the energy of the photon in the form of kinetic energy, and is sufficient to separate it from its atom and convert it into a projectile. This is stopped by ionization and excitation of the material
In the Compton effect the photon collides with an electron as if it were a clash between two elastic spheres. The secondary electron acquires only part of the energy of the photon and the rest takes it with another photon of lesser energy and diverted.
When an energy photon approaches the intense electric field of a nucleus, the production of pairs can happen. In this case the photon is transformed into an electron positron pair. Since the sum of the mass of the pair is 1.02 MeV, it cannot happen if the photon's energy is less than this amount. If the energy of the original photon is greater than 1.02 MeV, the surplus is distributed by the electron and the positron as kinetic energy, and the material can be ionized. The positron at the end of its path forms a positronium and then annihilates producing two annihilation photons, 0.51 MeV each.
The heat required to convert water is given as the product of the mas and the latent heat. 28.34 kJ heat must be removed from the water to change it into ice.
<h3>What is heat energy?</h3>
Heat energy is the product of mass, specific heat capacity, and temperature change. It is given as,

Given,
Mass of water = 456 gm
Specific heat capacity = 4.186 J / g K
Temperatutre change = 14.85 K
Substituting values above:

Therefore, 28.34 kJ of heat energy should be removed from the water.
Learn more about the heat here:
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Answer:
Explanation:
1. Please provide the enthalpy info - I will work on it with the info
2.
i) Reaction a should be modified to match the number of S in equation:
2S + 2O2 -> 2SO2 deltaH = -370kJ
ii) Reaction b should be written reversely to match the reactants of SO2:
2SO2 + O2 -> 2SO3 deltaH = 256kJ
iii) Adding the equations together:
2S + 3O2 -> 2SO3
iv) Enthalpy of the combined reaction = -370+256 = -114kJ
It is negative so the reaction is exothermic.
Answer:<em> A transfer of electrons occurs when fluorine and calcium react to form an ionic compound. This is because calcium is in group two and so forms ions with a two positive charge. ... A pairs of shared electrons makes one covalent bond. The compound formed is known as a molecule***</em>
The moles of oxygen gas (O2) that is needed is 4 moles
Explanation
2H2 +O2 → 2H2O
The moles of O2 is determined using the mole ratio of H2:O2
that is from equation above H2:O2 is 2:1
If the moles of H2 is 8 moles therefore the moles of O2
= 8 moles x 1/2 = 4 moles