Answer:
a . knowledge and existing theories .
b. falsifiable scope
Answer:
chemical change
Explanation:
chemical change requires energy in the form of heat or electricity.
Answer: 8 electrons
Explanation: Valence electrons are the electrons in the outermost shell of an atom and they are important in chemical reactions.
Atoms are <em>happy</em> when they follow the octet rule which states that 2 electrons can go in the first shell and 8 electrons can go in the other shells.
Electrons are happy when they have a full outer shell which usually needs to be 8 electrons. However, some of the smaller elements like helium are happy because they can hold a max of 2 electrons and helium has 2 electrons since it has 2 protons in its core as well as 2 electrons in its energy levels.
Move anywhere and can be anywhere while it is in that phase