NaHCO3(s) + HCl(aq) -> NaCl(aq) + H2O(l) + CO2(g) BE SURE TO USE THE CORRECTLY BALANCED EQUATION FOR THE REMAINDER OF THE ASSESSMENT.

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons? a) 6 b) 8 c) + 1 d) 12 e) 18

Place the elements below in order of decreasing ionization energy. aluminum(al) chlorine(cl) magnesium (mg) sulfur(s)