Answer:
are you talking about plant cells?
Explanation:
In chemistry, a single bond is a chemical bond between two atoms involving two valence electrons. That is, the atoms share one pair of electrons where the bond forms. Therefore, a single bond is a type of covalent bond.
Answer
the atomic number is also the proton number and so the number of protons are 6.
PWR stands for many things. Since you're talking about nuclear power reactors I think PWR stands for pressurized water reactor.
A pressurized water reactor follows many steps but the main goal is to obtain thermal energy from water.
Hope it helped,
BioTeacher101