10. Explain the relationship between the group number and the valence electrons of MAIN GROUP elements (Groups 1, 2, 13-18). *

Valence electrons are electrons that are in the outermost orbitals of an atom. In the periodic table the elements are divided into groups. All elements of the first main group have one valence electron. All elements of the second main group have two valence electrons. And so on:

a:

by the combination of an unlimited number of elements

it would be b. 6co2 + 6h2o --> c6h12o6 + 6o2