Question

decide whether the lewis structure proposed for each molecule is reasonable or not.

molecule proposed lewis structure is this a reasonable structure? if not, why not?

o₃
:o=o-o:
yes, its a reasonable structure.
no, the total number of valence electrons is wrong.
the correct number is:
no, some atoms have the wrong number of electrons around them.
the symbols of the problem atoms are:

sf₃⁻
:f-s-f :
:f :

yes, its a reasonable structure.
no, the total number of valence electrons is wrong.
the correct number is:
no, some atoms have the wrong number of electrons around them.
the symbols of the problem atoms are:

nh₂⁺
h-n=h ⁺
yes, its a reasonable struct
no, the total number of valence electrons is wrong.
the correct number is:
no, some atoms have the wrong number of electrons around them.
the symbols of the problem atoms are:

• if two or more atoms have the wrong number of valence electrons around them, just enter the chemical symbol for the atom as many times as necessary. for example, if two oxygen atoms have the wrong number of

Explanation:

\(O_3\)

Step1: Calculate valence electrons

O has 6 valence electrons. For \(O_3\), total valence electrons \(=3\times6 = 18\).
In the proposed structure:

• Double - bonded O: 6 electrons (4 as lone pairs and 2 in double bond)
• Single - bonded O: 7 electrons (6 as lone pairs and 1 in single bond)
• Central O: 7 electrons (4 as lone pairs and 3 in bonds)

Some atoms have wrong electron count.

\(SF_3^-\)

Step1: Calculate valence electrons

S has 6 valence electrons, F has 7 valence electrons. For \(SF_3^-\), total valence electrons \(=6 + 3\times7+1=28\).
In the proposed structure:

• S: 6 electrons (3 single bonds, no lone pairs shown properly. S should follow octet or expand octet. Here electron count around S is wrong as per proper Lewis structure rules considering formal charges and electron distribution)
• F: Each F should have 8 electrons (3 lone pairs and 1 bond). Assuming correct bonding in the given structure (if we just count electrons around atoms based on octet for F and proper for S), some atoms (S) have wrong electron count.

\(NH_2^+\)

Step1: Calculate valence electrons

N has 5 valence electrons, H has 1 valence electron. For \(NH_2^+\), total valence electrons \(=5 + 2\times1-1 = 6\).
In the proposed structure:

• N: 4 electrons (1 double bond and 2 single bonds shown wrongly. N should have 6 electrons around it in \(NH_2^+\) (considering formal charge \(N:5-(4) = + 1\), but the bonding is incorrect as H can only form single bonds). Some atoms (N and H, since H can't form double bonds) have wrong electron count.

Answer:

• For \(O_3\): No, some atoms have the wrong number of electrons around them. The symbols of the problem atoms are: \(O\) (central \(O\) and single - bonded \(O\))
• For \(SF_3^-\): No, some atoms have the wrong number of electrons around them. The symbols of the problem atoms are: \(S\)
• For \(NH_2^+\): No, some atoms have the wrong number of electrons around them. The symbols of the problem atoms are: \(N\) and \(H\)