Which of the following statements involving the periodic table is not correct?

A. The transition metals are in Groups 3 through 12 of the periodic table.
B. Uranium (Z = 92) is in the seventh period of the periodic table.
C. Alkali metal ions always have a charge of +1.
D. The element most similar to oxygen in its chemical behavior is fluorine.
E. The charge on monatomic halogen ions in binary ionic compounds is –1.
F. Silicon is a semimetal (metalloid).​