Chapter 10 Practice Test Flashcards Preview

AP Chemistry > Chapter 10 Practice Test > Flashcards

Flashcards in Chapter 10 Practice Test Deck (25)
Loading flashcards...
1
Q

Use the Lewis Dot structure for POCl3 to calculate the SN value for the central phosphorous atom.

A

4

2
Q

The Lewis Dot structure for water can be drawn in the following manner.

What is the steric number value and predicted geometric shape of water based on the SN value?

A

4; tetrahedral

3
Q

Which of the following best defines the term steric number (SN)?

A

The steric number is equal to the number of atoms in a molecule that are bonded to the central atom plus the number of lone pairs of electrons.

4
Q

What are the steric numbers for the central nitrogen atoms in these two molecules?

A

2, 2

5
Q

Which of the following molecules has only one lone pair on the central atom?

A

SO2

6
Q

Which of the following has a steric number of three and a bent molecular geometry?

A

O3

7
Q

What is the geometry of the molecule chlorine trifluoride, which has steric number 5?

A

T-shaped

8
Q

Which of the following has a square planar molecular geometry?

A

IF4−

9
Q

Which pair of molecules has the same steric number, but different shapes?

A

NO3− and O3

10
Q

Which statement best explains why the molecule in the diagram is polar?

A

The molecule is linear but is polar because the electronegativity of oxygen is greater than the electronegativity of sulfur

11
Q

The Lewis dot structure for oxalic acid is shown in the drawing. Which statement about the bond angles for oxalic acid is not true?

A

The H–O–C bond angle is 120°

12
Q

Which of the following best describes why phosphorous trichloride has a net dipole moment downward?

A

There is nothing on the “top” of the molecule to effectively cancel the downward dipole effect of the three Cl–P bonds

13
Q

What is the difference between a σ bond and a π bond?

A

A σ bond’s overlap occurs along the internuclear axis.

14
Q

Suppose that a theoretical gas atom has an electron configuration of 1s22s22p6. Which statement best describes this atom’s electron arrangement and theoretical reactivity with an atom that has an unpaired electron?

A

This atom has five orbitals, 1s, 2s, and three 2p orbitals. They each contain paired electrons. This atom will not display highly reactive tendencies, because its orbitals are already filled

15
Q

Which statement best describes the bonding in an O2 molecule?

A

O2 has one σ bond and one π bond

16
Q

What is hybridization of electron orbitals?

A

Hybridization of electron orbitals occurs when several atomic orbitals (such as s and p orbitals) of an atom combine to form (the same number of) new, hybrid orbitals. A promotion energy has to be involved in order for this event to occur.

17
Q

Which of the following statements correctly describes the geometry of the sp3 hybrids for molecules that have SN = 4?

A

tetrahedral

18
Q

Which of the following is equal to the total number of hybrid orbitals around a hybridized atom?

A

the steric number, SN

19
Q

Look at the electron configurations for an oxygen atom and a carbon atom.

Which statement best describes the bond tendencies for both of the atoms?

A

It appears that the oxygen atom can form two bonds because it has two unpaired electrons in the 2p orbitals. It appears that the carbon atom will want to alter its electron distribution in order to have more bonding opportunities with other atoms.

20
Q

The plot shows the atomic wave functions for two atoms involved in the formation of a molecule.

Which statement best describes this graph?

A

This plot shows the two atomic wave functions for two 1s orbitals involved in the formation of the H2 molecule

21
Q

Which statement best explains the difference between the electron distributions of a bonding orbital (e.g., H2 ) and an anti-bonding orbital (e.g., He2 )?

A

In a bonding orbital situation, the electron distribution is between the nuclei, because both nuclei want to share the electrons. In an anti- bonding circumstance, the electron distribution is around each atom. There is a void between the nuclei and the nuclei repel each other.

22
Q

Why is the energy ladder only helpful for elements that have numbers of 18 or less?

A

If the element had a higher atomic number, you would have to include orbital sites higher than 2p.

23
Q

Which of the following shows the correct order—from least to greatest energy—for the bond types found in 2s and 2p orbitals for the O2 molecule (for n = 2)?

A

one 2s σ bond, one 2s σ* bond, one 2p σ bond, two 2p π bonds, two 2p π* bonds, one 2p σ* bond

24
Q

Which statement best explains the idea of delocalized electrons?

A

Delocalized electrons are electrons that are spread out in a molecule (instead of being confined to atomic orbitals). This helps explain some of the unique physical properties (color, magnetism, and so on) of molecules.

25
Q

Which statement best explains why the bonding between the hydrogen and fluorine atoms occurs where it does?

A

The fluorine atom has such lower bonding energy levels that its 2px orbital is the one that is best poised for bonding with the 1s orbital of hydrogen

Decks in AP Chemistry Class (338):