HESI A2 Chemistry Updated for 2024-Graded A+

HESI A2 Chemistry Updated for 2024-Graded A+ atom basic building block of all molecules protons part of atom with a positive charge electrons part of atom with a negative electrical charge neutrons part of atom with no charge at all ion an atom that is electrically charged cation atom with a positive electrical charge anion atom with a negative electrical charge periods rows in the periodic table groups columns in the periodic table Group IA Group of Periodic table with a +1 charge. One electron in its outer shell. H Li Na K Rb Cs Fr Group IIA Group of Periodic table with a +2 charge. Two electrons in its outer shell Be Mg Ca Sr Ba Ra Group IIIA Group of Periodic table with a +3 charge. Three electrons in its outer shell B Al Ga In Ti Uut Group IVA Group of periodic table with either a +4 or a -4 charge. Four electrons in its outer shell C Si Ge Sn Pb Uuq Group VA Group of periodic table with a -3 charge N P As Sb Bi Uup