Question 1

Which of the following statements best explains why ionic compounds, such as NaCl, have high melting points?

Accepted Answer

Because the ions are held together by strong electrostatic forces.

Question 2

Which molecule below is an example of a pure covalent bond?

Accepted Answer

Cl2

Question 3

Given the electronegativities: Na = 0.9, Cl = 3.0, which type of bond is formed in NaCl?

Accepted Answer

Ionic

Question 4

Which of the following best describes the difference between electron affinity (EA) and electronegativity?

Accepted Answer

EA is measured for isolated atoms, while electronegativity is estimated for atoms in bonds.

Question 5

Which of the following molecules is an example of an expanded octet?

Accepted Answer

SF6

Question 6

What is the formal charge on the oxygen atom in the Lewis structure of $$\mathrm{H_2O}$$?

Accepted Answer

0

Question 7

Which of the following compounds is an example of an incomplete octet?

Accepted Answer

BF3

Question 8

In the Lewis structure of $$\mathrm{CO_2$}$$, how many double bonds are present?

Accepted Answer

Two

Question 9

Which of the following statements about bond length is correct?

Accepted Answer

Triple bonds are shorter than single bonds.

Question 10

Which of the following best describes a coordinate covalent bond?

Accepted Answer

A bond where both electrons come from the same atom.

Question 11

Which molecule below is a free radical due to having an odd number of electrons?

Accepted Answer

NO

Question 12

Which of the following is true about the physical properties of ionic and covalent compounds?

Accepted Answer

Covalent compounds have low melting points due to weak intermolecular forces.

Question 13

Which of the following is the correct procedure for drawing a Lewis structure for a polyatomic ion?

Accepted Answer

Add the charge to the total number of valence electrons.

Question 14

In the molecule $$\mathrm{NH_3$}$$, what is the oxidation number of nitrogen?

Accepted Answer

-3

Question 15

Which of the following best explains why F is the most electronegative element?

Accepted Answer

It has high electron affinity and high ionization energy.

Question 16

Which of the following molecules has resonance structures?

Accepted Answer

NO2

Question 17

For the ion $$\mathrm{OCN^-}$$, which Lewis structure is preferred based on formal charge?

Accepted Answer

[O–C≡N]$$^{-}$$, with the negative charge on O

Question 18

A student is asked to draw the Lewis structure for $$\mathrm{NH_4$^+}. $$How many valence electrons should be used?

Accepted Answer

7

Question 19

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

Accepted Answer

Elements in the second period generally obey the octet rule.

Question 20

Which of the following best describes the relationship between bond order and bond energy?

Accepted Answer

Higher bond order corresponds to higher bond energy.

chapter 7 part 1

Guida di studio - Domande di pratica