Multiple Choice
Which of the following molecules has only one lone (non-bonding) pair in its Lewis dot structure?
16
views
11. Bonding & Molecular Structure
Lewis Dot Structures: Exceptions
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
How many unshared (non-bonded) pairs of electrons are present in a molecule of NF_3?
A
10
B
8
C
12
D
6
Verified step by step guidance1
Determine the total number of valence electrons for the NF_3 molecule by adding the valence electrons of nitrogen and fluorine atoms. Nitrogen has 5 valence electrons, and each fluorine has 7 valence electrons. Since there are 3 fluorine atoms, calculate the total as \$5 + 3 \times 7$.
Draw the Lewis structure of NF_3 by placing nitrogen as the central atom and connecting it to the three fluorine atoms with single bonds. Each bond represents 2 shared electrons.
Assign the remaining valence electrons as lone pairs (unshared pairs) to complete the octet for each atom. Fluorine atoms typically have three lone pairs each, and nitrogen may have lone pairs as well.
Count the number of lone pairs on each atom. Remember that each lone pair consists of 2 electrons. Sum all lone pairs on nitrogen and fluorine atoms to find the total number of unshared electron pairs.
Multiply the total number of lone pairs by 2 to find the total number of unshared electrons, or simply count the lone pairs if the question asks for pairs. This will give you the total number of unshared (non-bonded) electron pairs in the NF_3 molecule.
2:05mWatch next
Master Lewis Dot Structures: Exceptions with a bite sized video explanation from Jules
Start learningRelated Videos
Related Practice
Lewis Dot Structures: Exceptions practice set
Problem sets built by lead tutorsExpert video explanations