Question 1

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electrons between two atoms.

Question 2

Which of the following electronegativity differences ($$\Delta EN) $$would result in a polar covalent bond?

Accepted Answer

$$0.5 \leq \Delta EN \u003c 1.9$$

Question 3

A molecule of carbon dioxide ($$\mathrm{CO_2$}) is $$nonpolar even though the bonds are polar. Why?

Accepted Answer

The molecule is symmetrical, so the bond dipoles cancel each other out.

Question 4

Which of the following molecules is expected to be polar?

Accepted Answer

$$\mathrm{NH_3$}$$

Question 5

What is the source of attraction in a covalent bond?

Accepted Answer

Attraction between shared electrons and the nuclei of both atoms.

Question 6

Which of the following is the correct formula for dinitrogen pentoxide?

Accepted Answer

$$\mathrm{N_2O_5}$$

Question 7

Which intermolecular force is present in all molecular compounds, regardless of polarity?

Accepted Answer

London dispersion forces

Question 8

Given the Lewis structure for water ($$\mathrm{H_2O}$$), what is the molecular shape according to VSEPR theory?

Accepted Answer

Bent

Question 9

Which of the following best explains why $$\mathrm{CH_4$} ($$methane) is nonpolar?

Accepted Answer

It has polar bonds but a symmetrical tetrahedral shape.

Question 10

What is the formal charge on the nitrogen atom in ammonia ($$\mathrm{NH_3$}$$)?

Accepted Answer

$$0$$

Question 11

Which of the following compounds contains a triple covalent bond?

Accepted Answer

$$\mathrm{N_2$}$$

Question 12

Which of the following best describes a resonance structure?

Accepted Answer

A structure that represents one of two or more valid Lewis structures for a molecule.

Question 13

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

Accepted Answer

$$\mathrm{CO_2$}$$

Question 14

Which of the following is the correct name for $$\mathrm{$$PCl_3$$}$$?

Accepted Answer

Phosphorus trichloride

Question 15

A molecule has two different atoms bonded to a central atom and one lone pair on the central atom. What is the most likely shape of the molecule?

Accepted Answer

Bent

Question 16

Which of the following statements about intermolecular forces is correct?

Accepted Answer

London dispersion forces are present in all molecules, including nonpolar ones.

Question 17

Which of the following best describes a nonpolar molecule?

Accepted Answer

A molecule with a symmetrical shape and nonpolar bonds.

Question 18

Which of the following is the correct formula for sulfur hexafluoride?

Accepted Answer

$$\mathrm{SF_6$}$$

Question 19

A mass spectrometry analysis of a molecule shows a peak at a mass corresponding to the loss of a methyl group ($$\mathrm{CH_3$}). $$What does this suggest about the structure of the molecule?

Accepted Answer

The molecule contains a methyl group attached to the central atom.

Question 20

Which of the following molecules is most likely to have hydrogen bonding as its strongest intermolecular force?

Accepted Answer

$$\mathrm{H_2O}$$

Covalent Bonding, Polarity, and Molecular Structure: Study Notes for Introductory Chemistry

Guida di studio - Domande di pratica

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