Given the general chemical equation A + 2B → 2C + D, what is the limiting reactant if 2.0 mol of A are exposed to 6.2 mol of B?

a. A
b. B
с. С
d. D

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

catya your not at all which answer i've seen you do this on another question!