$$6 \times 2 + 6 \times 1 = 18$$

Question 1

Which of the following molecules has a linear molecular geometry according to VSEPR theory?

Accepted Answer

CO\_2

Question 2

How many valence electrons are present in a molecule of SO\_2?

Accepted Answer

$$6 	imes 2 + 6 	imes 1 = 18$$

Question 3

Which of the following statements best explains why H\_2O is a polar molecule?

Accepted Answer

The molecule is bent and the dipoles do not cancel out.

Question 4

What is the correct Lewis structure for CO\_2?

Accepted Answer

O=C=O, with each O atom having two lone pairs

Question 5

Which of the following molecules contains a triple bond in its Lewis structure?

Accepted Answer

N\_2

Question 6

A molecule of NH\_3 (ammonia) has which of the following molecular shapes and bond angles?

Accepted Answer

Trigonal pyramidal, $$\sim 107^\circ$$

Question 7

Which of the following best describes the difference between polar and nonpolar covalent bonds?

Accepted Answer

Polar covalent bonds have unequal sharing of electrons due to differences in electronegativity.

Question 8

Which of the following molecules is nonpolar despite having polar bonds?

Accepted Answer

CO\_2

Question 9

How many bonds does nitrogen typically form to achieve a stable octet?

Accepted Answer

3

Question 10

Which of the following best describes the role of lone pairs in determining molecular shape according to VSEPR theory?

Accepted Answer

Lone pairs repel bonding pairs, altering bond angles and molecular geometry.

Question 11

Which of the following statements about the Lewis structure of PO\_$$4^{3-} is $$correct?

Accepted Answer

The structure has 32 valence electrons, with P at the center and each O atom bonded to P, and three extra electrons for the charge.

Question 12

Which of the following intermolecular forces is the strongest?

Accepted Answer

Hydrogen bonding

Question 13

Which of the following best explains why NaCl is classified as an ionic compound?

Accepted Answer

It has a large electronegativity difference between Na and Cl, resulting in electron transfer.

Question 14

Which of the following changes of state is exothermic?

Accepted Answer

Condensation

Question 15

A molecule has three bond groups and no lone pairs on the central atom. What is its molecular geometry and bond angle?

Accepted Answer

Trigonal planar, $$120^\circ$$

Question 16

Which of the following best describes London dispersion forces?

Accepted Answer

Temporary dipoles induced in all atoms and molecules, increasing with atomic size

Question 17

Which of the following molecules would you expect to have the highest boiling point?

Accepted Answer

H\_2O

Question 18

Which of the following is the correct order of bond polarity from least to most polar?

Accepted Answer

CH\_4 \u003c NH\_3 \u003c H\_2O \u003c NaCl

Question 19

Which of the following best explains why CO\_2 is nonpolar even though it contains polar bonds?

Accepted Answer

The molecule is linear and the bond dipoles cancel out.

Question 20

Which of the following statements about endothermic and exothermic processes is correct?

Accepted Answer

Endothermic processes absorb heat, while exothermic processes release heat.

Covalent Bonding, Lewis Structures, Molecular Geometry, Polarity, and Intermolecular Forces

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