Answer:
The number of electrons in the outermost shell of an atom determines its reactivity. Noble gases have low reactivity because they have full electron shells. Halogens are highly reactive because they readily gain an electron to fill their outermost shell.
Explanation:
I hope this helped!
I would say developed technologies which somehow were lost
like the stone age: the stone hammer, who used that afterwards in the roman empire era and stuff?
Answer:
i would assume that it would be (a)
Explanation:
The Sun generates its energy by nuclear fusion
NUCLEAR FISSION is when the heavy atom is split
fusion energy is scientifically feasible. Plasma conditions that are very close to those required in a fusion reactor are now routinely reached in experiments
mass gets lost is nuclear fusion
so (a) is the most accurate