Answer:Chemical reactions often involve changes in energy due to the breaking and formation of bonds. Reactions in which energy is released are exothermic reactions, while those that take in heat energy are endothermic. exothermicA description of a chemical reaction that releases heat energy to its surroundings.
Formula 1!!!!!!!!!!!!!!!!!!!!!!!!!!
Answer:
The nuclear charge increases, but the number of inner shielding electrons stays the same.
Explanation:
Their shielding does not change, so the effective nuclear charge — the charge felt by a valence electron — increases.
The valence electrons are pulled closer to the nucleus, decreasing the atomic radius.
For example, consider the elements of Period 3.

The number of protons increases as you go from one element to the next, but the number of inner electrons is constant.
Answer:
no of neutron = atomic mass - atomic number
Explanation:
here
atomic mass = 64
atomic number = 30
no of neutron = <span>64−30</span>
no of neutron = 34
I think it’s B but not 100% sure