Which statements about hydrogen are true?
I. H has a lower ionization energy than He.
II. H^- is smaller than H.
III. H has a higher effective nuclear charge than He.
IV. H is always a metal.
V. H does not have a second ionization energy.

Question

Quizplus · Accepted Answer

I. True. Hydrogen has one electron and He has two, so hydrogen's electron is held more tightly to its nucleus. II. False. H^- is not a valid chemical element or ion, so it cannot be compared to H. III. True. Hydrogen's electron is closer to its nucleus, so there is a greater attraction and effective nuclear charge. IV. False. Hydrogen can exhibit both metallic and nonmetallic behavior, depending on the conditions. V. True. Hydrogen's lone electron is lost in ionization, leaving the atom with no further electrons to remove.

Which Statements About Hydrogen Are True