AP Chemistry

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 sub shell of nitrogen atoms.

• Nitrogen atoms have a smaller nuclear charge than oxygen atoms.

Answer explanation

"Nuclear charge" = charge of the nucleus. A greater nuclear charge will result in a greater attraction to the 1s electrons, and therefore more energy will be required to remove those electrons.

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

How many pi bonds does this have? 

• 1

• 2

• 3

• 4

How many sigma and pi bonds does this have?

• 1 sigma and 1 pi

• 2 sigma and 1 pi

• 1 sigma and 2 pi

• 2 sigma and 2 pi

A sample of a hard, solid binary compound at room temperature did not conduct electricity as a pure solid but became highly conductive when dissolved in water. Which of the following types of interactions is most likely found between the particles in the substance?

• Ionic bonds

• Metallic bonds

• Covalent bonds

• Hydrogen bonds

Tags

NGSS.HS-PS1-3

Match the following properties with their classification as either an intensive or extensive property.

• Temperature at which an object changes from solid to liquid

• Metallic

• Amount of matter in an object

• Mass

• Appearance of an object

• Melting point

• Color of an object

• Silver

Which element is represented by this PES graph?

• argon

• potassium

• calcium

• scandium

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which molecule would have this molecular geometry?

• BF₃

• CH₄

• PCl₅

• CO₂

Who could this be? 

• CO₂

• NH₃

• H₂S

• CH₄

Which substance would have the weakest intermolecular forces of attraction?

• CH₄

• NaCl

• H₂O

• MgF₂

Intermolecular force present in HCl?

• dipole dipole

• dispersion

• H-bond

• ionic