Question 1

Which of the following statements best explains why the bond length increases from F$$_2 to I$_2 as $$shown in the image?

Accepted Answer

The atomic radius increases down the group, so the nuclei are farther apart in larger atoms.

Question 2

Given the Lewis structures for water, ammonia, and methane, which molecule has the greatest number of lone pairs on the central atom?

Accepted Answer

Water

Question 3

Which molecule shown in the dipole moment images is expected to have the highest boiling point, and why?

Accepted Answer

Water, because its strong dipole moment leads to strong intermolecular forces.

Question 4

Which of the following best describes the geometry and shape of ammonia (NH$$_3) $$according to VSEPR theory?

Accepted Answer

Geometry: Tetrahedral; Shape: Trigonal pyramidal

Question 5

Which of the following molecules is nonpolar despite having polar bonds, as shown in the images?

Accepted Answer

Carbon dioxide (CO$$_2)$$

Question 6

What is the formal charge on the central sulfur atom in the SO$$_2$$ Lewis structure with two double bonds?

Accepted Answer

$$0$$

Question 7

Which of the following best explains why NaCl forms a solid lattice structure as shown in the image?

Accepted Answer

Strong electrostatic attraction between oppositely charged ions leads to a stable lattice.

Question 8

Which molecule has a bond angle closest to $$109.5^{\circ}$$, and why?

Accepted Answer

Methane (CH$$_4$$), because it has four bonding pairs and no lone pairs.

Question 9

Which of the following statements about resonance structures is correct?

Accepted Answer

Resonance structures differ only in the arrangement of electrons, not the positions of atoms.

Question 10

Which of the following molecules has a square planar shape according to VSEPR theory?

Accepted Answer

XeF$$_4$$

Question 11

What is the relationship between bond energy and bond length for covalent bonds?

Accepted Answer

Bond energy decreases as bond length increases.

Question 12

Which of the following best describes the effect of lone pairs on bond angles in molecules?

Accepted Answer

Lone pairs decrease bond angles between bonding pairs due to increased repulsion.

Question 13

Which molecule is expected to have the largest dipole moment based on the images and your knowledge of molecular structure?

Accepted Answer

Water (H$$_2O)$$

Question 14

Which of the following is true about the electron configuration of a neutral lithium atom?

Accepted Answer

It is $$1s^2$$ $$2s^1.$$

Question 15

Which of the following molecules has a seesaw shape according to VSEPR theory?

Accepted Answer

SF$$_4$$

Question 16

What is the total number of valence electrons in the nitrate ion (NO$$_3^-$$)?

Accepted Answer

$$24$$

Question 17

Which of the following best explains why water is a liquid at room temperature while methane is a gas?

Accepted Answer

Water is polar and forms strong intermolecular hydrogen bonds.

Question 18

Which of the following statements about the octet rule is correct?

Accepted Answer

Atoms tend to form bonds to achieve eight electrons in their valence shell.

Question 19

Which of the following best describes the geometry and shape of SF$$_6$$?

Accepted Answer

Geometry: Octahedral; Shape: Octahedral

Covalent Bonding, Molecular Structure, and VSEPR Theory: A General Chemistry Study Guide

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