Which of the following reactions is correctly balanced? 3 Ca + 1 N2 → Ca3N2
O 2 P2 + 3 H2 → 2 PH3
O 2 HgBr → 1 Hg + 1 Br2
O 2 Sr + 102 — 1 sro

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 a property of a double replacement reaction

Which process describes vaporization that takes place below the surface of a liquid? condensation melting boiling evaporation