d and f BLOCK ELEMENTS

Why does copper's positive E°(M2+/M) value prevent it from liberating H2 from acids?

• Because copper does not form ions.
• Because the reaction has a positive cell potential, making it spontaneous.
• Because copper is less reactive than hydrogen.
• Because the reaction Cu + 2H+ → Cu2+ + H2 would have a negative cell potential, making it non-spontaneous.

According to the text, which type of acids can react with copper metal?

• Only dilute acids.
• Any type of acid.
• Only non-oxidizing acids.
• Only oxidizing acids.

What is the main reason provided in the text for copper's positive E°(M2+/M) value?

• Its low atomization enthalpy is balanced by its high hydration enthalpy.
• Its high atomization enthalpy is balanced by its equally high hydration enthalpy.
• Its low atomization enthalpy is not balanced by its hydration enthalpy.
• Its high atomization enthalpy (ΔaH°) is not sufficiently balanced by its low hydration enthalpy (ΔhydH°).

Why is the statement 'only the sum of first and second ionization enthalpies determines the E° trend' an oversimplification?

• Because ionization enthalpies are always constant.
• Because hydration enthalpy is the only important factor.
• Because atomization enthalpy is always negligible.
• Because it ignores the significant contributions of atomization enthalpy and hydration enthalpy, as well as specific electronic effects.

If the atomization enthalpy of a metal M were significantly lower, how would this likely affect its E°(M2+/M) value, assuming other factors remain constant?

• The E°(M2+/M) value would likely become less negative.
• The E°(M2+/M) value would remain unchanged.
• The E°(M2+/M) value would become positive.
• The E°(M2+/M) value would likely become more negative.