Question 1

Which of the following best explains why water has a high surface tension compared to most other liquids?

Accepted Answer

Water molecules form strong hydrogen bonds with each other, creating a cohesive surface layer.

Question 2

A student observes that a drop of oil does not spread out on a glass slide, while a drop of water does. Which statement best explains this observation?

Accepted Answer

Oil is nonpolar and does not interact strongly with the polar glass surface, while water is polar and forms hydrogen bonds with the glass.

Question 3

Which of the following correctly lists the four main types of intermolecular forces from strongest to weakest?

Accepted Answer

Ion-dipole \u003e Hydrogen bonding \u003e Dipole-dipole \u003e London dispersion

Question 4

What is the primary reason sodium stearate is effective at cleaning oily surfaces?

Accepted Answer

It is amphipathic, allowing it to form micelles that trap nonpolar oil molecules inside and interact with water on the outside.

Question 5

Which of the following best describes a micelle?

Accepted Answer

A spherical structure formed by amphipathic molecules in water, with hydrophobic tails inward and hydrophilic heads outward.

Question 6

According to VSEPR theory, what is the molecular geometry of $$\mathrm{NH_3$}$$?

Accepted Answer

Trigonal pyramidal

Question 7

Which of the following molecules is most likely to have only London dispersion forces as its primary intermolecular force?

Accepted Answer

$$\mathrm{C_2H_6}$$

Question 8

How does the length of a nonpolar molecule affect the strength of its intermolecular forces?

Accepted Answer

Longer nonpolar molecules have stronger London dispersion forces due to increased surface area.

Question 9

Which of the following best explains why a surfactant reduces the surface tension of water?

Accepted Answer

Surfactants disrupt hydrogen bonding between water molecules at the surface.

Question 10

Which of the following pairs of substances is most likely to be miscible (able to mix completely)?

Accepted Answer

$$\mathrm{CH_3Br}$$ and $$\mathrm{NH_3$}$$

Question 11

Which of the following is NOT a major molecular geometry predicted by VSEPR theory?

Accepted Answer

Square planar

Question 12

What is the key difference between electron group geometry and molecular geometry?

Accepted Answer

Electron group geometry considers all electron groups (bonds and lone pairs), while molecular geometry considers only the arrangement of atoms.

Question 13

Which of the following molecules is polar due to its molecular geometry and bond dipoles?

Accepted Answer

$$\mathrm{CH_3Cl}$$

Question 14

A student draws the Lewis structure for $$\mathrm{CO_2$}$$ and $$\mathrm{CH_4$}. $$Which statement is correct regarding their ability to mix?

Accepted Answer

Both are nonpolar and will mix due to similar intermolecular forces.

Question 15

Which intermolecular force is primarily responsible for the high boiling point of water?

Accepted Answer

Hydrogen bonding

Question 16

Which of the following best describes the process of using dipoles to determine the overall polarity of a molecule?

Accepted Answer

Sum the individual bond dipoles as vectors; if they do not cancel, the molecule is polar.

Question 17

Which of the following is an example of an amphipathic molecule?

Accepted Answer

Sodium stearate

Question 18

A molecule has a tetrahedral electron group geometry but a trigonal pyramidal molecular geometry. Which of the following molecules fits this description?

Accepted Answer

$$\mathrm{NH_3$}$$

Question 19

Which of the following best explains why sodium stearate forms micelles in water?

Accepted Answer

Its hydrophobic tail avoids water while its hydrophilic head interacts with water, leading to spherical micelle formation.

Question 20

Which of the following statements about VSEPR theory is correct?

Accepted Answer

VSEPR theory predicts molecular shapes based on the repulsion between electron groups around a central atom.

Study Guide for Molecular Geometry & Intermolecular Forces

Guida di studio - Domande di pratica

Study guide - Flashcard