Answer:
Nuclear Reaction, 8, have very high melting and boiling points
Step-by-step explanation:
Changing Uranium into Bismuth is a Nuclear Reaction as the amount of protons are changing. To change an atom into another atom, fusion or fission must occur, two different types of nuclear reactions.
The maximum number of electrons in the second principal energy level is 8 because of the octet rule.
Covalent network solids have high melting and boiling points because they are bonded by covalent bonds that are very strong. High levels of heat are needed to break these bonds.
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