1. The vertical columns on the periodic table are called groups or families because of their similar chemical behavior.
2. All the members of a family of elements have the same number of valence electrons and similar chemical properties.
3. The horizontal rows on the periodic table are called periods.
I think it might be immortal? Not sure what is your point
Answer: An atom valence electron shell determines its chemical reactivity.
Explanation:
An atom's valence electron shell determines its chemical reactivity. The amount of electrons in the outermost shell of an atom is its valence electron and it determines how reactive the atom is.
The reactivity of an atom depends on the number of electrons in its outermost shell. Atoms that has their outermost electrons full e.g noble gases like argon, krypton etc are unreactive because there is no room for the atom to donate or accept any electron.
Elements like sodium and chlorine are reactive because they possesses 1 and 7 electrons in their outermost shell respectively as such they can donate and accept electrons making them reactive elements.
a hot cup because if a hot cup is hotter it's been in the sun too long
Construction lines should not be erased, because construction lines serve as a guide for you and for your drawing. Construction lines are used as references in positioning objects or other lines in your work. Construction lines must be easily seen and easy to be erased.
