Question 1

Which of the following best explains why noble gases are generally unreactive?

Accepted Answer

They have a full octet of electrons in their outermost shell, making them stable.

Question 2

What is the correct Lewis (electron-dot) symbol for a chlorine atom?

Accepted Answer

$$ \mathrm{Cl} \cdot \cdot \cdot \cdot \cdot \cdot \cdot $$

Question 3

Sodium reacts with chlorine to form sodium chloride. Which type of bond is formed and why?

Accepted Answer

An ionic bond, because sodium transfers an electron to chlorine, resulting in oppositely charged ions.

Question 4

Which of the following ions has the same electron configuration as neon ($$\mathrm{Ne}$$)?

Accepted Answer

$$\mathrm{Na}^+$$

Question 5

According to the octet rule, how many valence electrons do atoms generally seek to have in their outer shell?

Accepted Answer

$$8$$

Question 6

What is the correct formula for magnesium oxide, given the charges of the ions involved?

Accepted Answer

$$\mathrm{MgO}$$

Question 7

Which of the following is the correct name for the compound $$\mathrm{K}_2\mathrm{S}$$?

Accepted Answer

Potassium sulfide

Question 8

Which of the following compounds contains a polyatomic ion?

Accepted Answer

$$\mathrm{Ca(NO_3$)_2}$$

Question 9

What is the correct name for $$\mathrm{NH_4$}_2\mathrm{SO_4$}$$?

Accepted Answer

Ammonium sulfate

Question 10

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed by the sharing of electron pairs between atoms.

Question 11

What is the correct name for $$\mathrm{P_2O_3}$$?

Accepted Answer

Diphosphorus trioxide

Question 12

Which of the following pairs of elements is most likely to form a polar covalent bond?

Accepted Answer

Hydrogen and chlorine

Question 13

Given the electronegativity difference between two atoms is $$1.5$$, what type of bond will they most likely form?

Accepted Answer

Polar covalent

Question 14

Which of the following is a correct guideline for drawing Lewis structures?

Accepted Answer

Count the total number of valence electrons for all atoms in the molecule.

Question 15

Which molecule is a free radical?

Accepted Answer

$$\mathrm{NO}$$

Question 16

According to VSEPR theory, what is the shape of a molecule with four electron sets (all bonds) around the central atom?

Accepted Answer

Tetrahedral

Question 17

Which of the following conditions must be met for a molecule to be polar?

Accepted Answer

It must have polar bonds and the bonds must be arranged so that a separation of charge exists.

Question 18

Which of the following best describes the difference between an ion and an atom?

Accepted Answer

An ion has a net electrical charge due to the loss or gain of electrons, while an atom is electrically neutral.

Question 19

Which of the following is the correct formula for calcium nitrate?

Accepted Answer

$$\mathrm{Ca(NO_3$)_2}$$

Question 20

A patient is given a medication containing the sulfate ion. What is the formula for the sulfate ion?

Accepted Answer

$$\mathrm{SO_4$}^{2-}$$

Chemical Bonds: Structure, Types, and Properties

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