U2: Lewis Structures: Mastery Test

In a molecule of methane, carbon (having four valence electrons) binds to four hydrogen atoms. How many lone pairs of electrons will be represented in the Lewis structure of methane?

• four

• two

• one

• zero

What is the first step in creating a Lewis structure for a molecule?

• counting the number of lone pairs of electrons

• counting the number of electron orbitals

• counting the number of single bonds

• counting the number of valence electrons

Tags

NGSS.HS-PS1-1

Select the correct answer. How many lone pairs of electrons are represented in the Lewis structure of a nitrate ion (NO₃⁻)?

• 4

• 8

• 12

• 24

Select the correct answer. What is the total number of electrons shown in this Lewis structure of carbon dioxide?

• 8

• 12

• 16

• 24

Tags

NGSS.MS-PS1-1

Which is the correct Lewis structure for fluorine, which is a group 7A element?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

Which is the correct Lewis structure for carbon tetrabromide (CBr₄), in which a central carbon atom is bound to four atoms of the group 7A element bromine?

• A

• B

• C

• D

Which is the correct Lewis structure for carbon monoxide?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Select the correct answer. Nitrogen has five valence electrons. What is the correct Lewis structure for nitrogen?

• A.

• B.

• C.

• D.

Which is the correct Lewis structure for carbononitridic chloride (CNCl)?

• A

• B

• C

• D

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Select the correct answer. Which is the correct Lewis structure for acetylene (C₂H₂)?

• A

• B

• C

• D