Unit 2 MC Review

Which of the following best helps to account for the fact that the F^- ion is smaller than the O^2- ion?

• F^- has a larger nuclear mass than O^2- has.

• F^- has a larger nuclear charge than O^2- has.

• F^- has more electrons than O^2- has.

• F^- is more electronegative than O^2- is.

• F^- is more polarizable than O^2- is.

Consider atoms of the following elements. Assume that the atoms are in the ground state.

The atom that contains only one electron in the highest occupied energy sublevel

• S

• Ca

• Ga

• Sb

• Br

Which of the following best helps to explain why the electron affinity of Br has a greater magnitude than that of I?

• Br has a lower electronegativity than I does.

• Br has a lower ionization energy than I does.

• An added electron would go into a new shell in Br but not in I .

• There is a greater attraction between an added electron and the nucleus in Br than in I .

The photoelectron spectra above show the energy required to remove a 1s electron from a nitrogen atom and from an oxygen atom. Which of the following statements best accounts for the peak in the upper spectrum being to the right of the peak in the lower spectrum?

• Nitrogen atoms have a half-filled p subshell.

• There are more electron-electron repulsions in oxygen atoms than in nitrogen atoms.

• Electrons in the p subshell of oxygen atoms provide more shielding than electrons in the p subshell of nitrogen atoms

• Nitrogen atoms have a smaller nuclear charge than oxygen atoms

Which of the following is the electron configuration of an excited atom that is likely to emit a quantum of energy?

• 1s² 2s²2p⁶ 3s²3p¹

• 1s² 2s²2p⁶ 3s²3p⁵

• 1s² 2s²2p⁶ 3s²

• 1s² 2s²2p⁶ 3s¹

• 1s² 2s²2p⁶ 3s¹3p¹

Which of the following is the ground-state electron configuration of the F⁻ ion?

• 1s²2s²2p⁴

• 1s²2s²2p⁵

• 1s²2s²2p⁶

• 1s²2s²2p⁶3s²3p⁶

Based on the ionization energies of element X given in the table above, which of the following is most likely the empirical formula of an oxide of element X?

• XO₂

• X₂O

• X₂O₃

• X₂O₅

The first five ionization energies of a second-period element are listed in the table above. Which of the following correctly identifies the element and best explains the data in the table?

• B, because it has five core electrons

• B, because it has three valence electrons

• N, because it has five valence electrons

• N, because it has three electrons in the p sublevel

Which of the following Lewis diagrams best represents the bonding in the N₂O molecule, considering formal charges?

• 
• 
• 
• 

A sample containing atoms of C and F was analyzed using x-ray photoelectron spectroscopy. The portion of the spectrum showing the 1s peaks for atoms of the two elements is shown above. Which of the following correctly identifies the 1s peak for the F atoms and provides an appropriate explanation?

• Peak X, because F has a smaller first ionization energy than C has

• Peak X, because F has a greater nuclear charge than C has

• Peak Y, because F is more electronegative than C is

• Peak Y, because F has a smaller atomic radius than C has