The Lewis structure for the chlorate ion is b :0:

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The Lewis structure for the chlorate ion is b :0: Calculate the formal charge on the chlorine (Cl) atom. Express your answer as an integer. ? View Available Hint(s) formal charge on Cl = Submit Part B Calculate the formal charge on each of the oxygen (O) atoms labeled a, b, and c in the following Lewis structure. b :0: :0 Express your answers as integers separated by commas. View Available Hint(s) formal charge on Oa, Ob, Oc = Submit Formal charges to predict the most stable structure The interactive activity shows how to calculate the formal charge of atoms in a structure. These formal charges can be used to predict the resonance structure that contributes most to the stability of a molecule or ion. The structure with the lowest formal charge on each atom and which places the negative charge on the most electronegative atom is generally the most stable. Part C What are the formal charges on the sulfur (S), carbon (C), and nitrogen (N) atoms, respectively, in the resonance structure that contributes most to the stability of the thiocyanate ion, SCN-? The possible resonance structures for the thiocyanate ion, SCN-, are (S=C=N’ :5-c=ij’ [:S=C-N:I’ Structure A Structure B Structure C Express your answers as integers separated by commas. ? View Available Hint(s) formal charge on sulfur (S), carbon (C) and nitrogen (N) atoms =

The Correct Answer and Explanation is :

Part A: Formal Charge on Chlorine (Cl) in the Chlorate Ion

For the chlorate ion (ClO₃⁻), the chlorine atom is typically surrounded by three oxygen atoms, with one of the oxygens carrying a negative charge. The Lewis structure would show chlorine with a single bond to two oxygens and a double bond to one oxygen. We can calculate the formal charge (FC) using the formula:

[
FC = V – (L + \frac{1}{2}B)
]
Where:

  • (V) = Valence electrons of the atom (Chlorine has 7 valence electrons).
  • (L) = Lone pairs of electrons on the atom (Chlorine has no lone pairs in this case).
  • (B) = Number of bonding electrons (The bonds with oxygen atoms).

The formal charge on chlorine in chlorate is calculated as follows:

  • Chlorine has 7 valence electrons.
  • Chlorine is involved in bonds with three oxygen atoms. The bonds consist of one double bond and two single bonds (6 electrons total).

Thus, the formal charge on chlorine in the chlorate ion is:
[
FC_{\text{Cl}} = 7 – (0 + \frac{6}{2}) = 7 – 3 = +1
]
So, the formal charge on the chlorine atom is +1.

Part B: Formal Charges on Oxygen (O) Atoms in the Chlorate Ion

For the three oxygen atoms in the chlorate ion, we can apply the same formula to each:

  1. Oxygen atom (Oa) with a double bond to chlorine:
  • Oxygen has 6 valence electrons.
  • It is involved in a double bond (4 electrons).
  • There are 2 lone pairs on this oxygen (4 electrons). [
    FC_{\text{Oa}} = 6 – (4 + \frac{4}{2}) = 6 – 6 = 0
    ]
  1. Oxygen atom (Ob) with a single bond to chlorine and carrying a negative charge:
  • Oxygen has 6 valence electrons.
  • It is involved in a single bond (2 electrons).
  • It has 3 lone pairs (6 electrons). [
    FC_{\text{Ob}} = 6 – (6 + \frac{2}{2}) = 6 – 7 = -1
    ]
  1. Oxygen atom (Oc) with a single bond to chlorine:
  • Oxygen has 6 valence electrons.
  • It is involved in a single bond (2 electrons).
  • It has 3 lone pairs (6 electrons). [
    FC_{\text{Oc}} = 6 – (6 + \frac{2}{2}) = 6 – 7 = -1
    ]

Thus, the formal charges on the oxygen atoms are: 0, -1, -1.

Part C: Formal Charges in the Thiocyanate Ion (SCN⁻)

The thiocyanate ion (SCN⁻) has three possible resonance structures. To calculate the formal charges, we will examine each atom in the three structures:

  1. Structure A (S=C=N⁻):
  • Sulfur (S):
    • Sulfur has 6 valence electrons.
    • It is involved in a double bond with carbon (4 electrons).
    • It has 2 lone pairs (4 electrons).
      [
      FC_{\text{S}} = 6 – (4 + \frac{4}{2}) = 6 – 6 = 0
      ]
  • Carbon (C):
    • Carbon has 4 valence electrons.
    • It is involved in a double bond with sulfur and a single bond with nitrogen (4 electrons).
      [
      FC_{\text{C}} = 4 – (0 + \frac{4}{2}) = 4 – 4 = 0
      ]
  • Nitrogen (N):
    • Nitrogen has 5 valence electrons.
    • It is involved in a single bond with carbon (2 electrons).
    • It has 3 lone pairs (6 electrons).
      [
      FC_{\text{N}} = 5 – (6 + \frac{2}{2}) = 5 – 7 = -1
      ]
  1. Structure B (S≡C-N⁻):
  • Sulfur (S):
    [
    FC_{\text{S}} = 6 – (6 + \frac{6}{2}) = 6 – 9 = -1
    ]
  • Carbon (C):
    [
    FC_{\text{C}} = 4 – (0 + \frac{6}{2}) = 4 – 6 = -2
    ]
  • Nitrogen (N):
    [
    FC_{\text{N}} = 5 – (6 + \frac{2}{2}) = 5 – 7 = -1
    ]
  1. Structure C (S=C≡N):
  • Sulfur (S):
    [
    FC_{\text{S}} = 6 – (4 + \frac{4}{2}) = 6 – 6 = 0
    ]
  • Carbon (C):
    [
    FC_{\text{C}} = 4 – (0 + \frac{4}{2}) = 4 – 4 = 0
    ]
  • Nitrogen (N):
    [
    FC_{\text{N}} = 5 – (6 + \frac{2}{2}) = 5 – 7 = -1
    ]

The resonance structure with the most stable configuration has the formal charges on sulfur (S) = 0, carbon (C) = 0, and nitrogen (N) = -1.

Summary of Formal Charges

  • Chlorate Ion (ClO₃⁻):
  • Chlorine (Cl): +1
  • Oxygen (O): 0, -1, -1
  • Thiocyanate Ion (SCN⁻):
  • Sulfur (S): 0
  • Carbon (C): 0
  • Nitrogen (N): -1

Now, I’ll generate an image of the chlorate ion and the thiocyanate ion to visualize their structures.

Here is the image showing the Lewis structures for both the chlorate ion (ClO₃⁻) and the thiocyanate ion (SCN⁻), with the formal charges highlighted on each atom. Let me know if you’d like further clarifications!

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