Positron emission = emission of a positron and a neutrino when a
proton is convert into a neutron. The total number of particles in the
nucleus doesn't change, -1 proton +1 neutron
It's a spontaneous reaction for some nucleus.
eg:
Positron = e+
Neutrino=ve
O-15 --> N-15 + e+ +ve
Electron
capture= A nucleus absorb an electron while a proton is convert in a
neutron and emit a neutrino. The total number of particles in the
nucleus doesn't change, -1 proton +1 neutron
eg:
Al-26 +e- --> Mg-26 + ve
Electron
capture and positron emission are two mechanisms to explain the decay
of some unstable isotopes. Electron capture is usually observed when the
energy difference between the initial and final state is low. Mainly
because of the larger amount of kinetic energy need for the expulsion
two particles with the positron emission mechanism.
Answer:
Weak bonds require less energy to form than strong bonds
Explanation:
According to Coulomb's law, the force between two species is inversely proportional to the distance between them. That said, the bigger the atoms are, the greater the bond length should be to form a molecule.
As a result, for a greater bond length, the attraction force is lower than for a shorter bond length. This implies that large atoms would form weak bonds and small atoms would form strong bonds.
Bond energy is defined as the amount of energy required to break the bond. If a bond is weak, it would require a low amount of energy to break it. This is also true for energy of formation, as it's the same process taking place in the opposite direction.
True. Our earth Is getting hotter due to global warming.