Consider the carbonyl sulfide OCS where the carbon atom is the central atom.

1) Draw the three resonance structures for this molecule.

2) What is the most stable resonance form? Explain.

3) A C=O double bond has an average bond length of 124 pm. What can you say about the CO bond length of the carbonyl sulfide?

4) Is OCS polar? If yes, draw the dipole moment of the most stable resonance form.

Question

Consider the carbonyl sulfide OCS where the carbon atom is the central atom.

1) Draw the three resonance structures for this molecule.

2) What is the most stable resonance form? Explain.

3) A C=O double bond has an average bond length of 124 pm. What can you say about the CO bond length of the carbonyl sulfide?

4) Is OCS polar? If yes, draw the dipole moment of the most stable resonance form.

| General Chemistry 1

Accepted Answer

1)

2)

No formal charges

3) In the most stable resonance form of OCS, CO is a double bond so its length is close to 124 pm.

Electronegativity of O > electronegativity of S. The second more stable resonance form is :

CO is a single bond in this form

⇒ The CO bond length of the carbonyl sulfide is < 124 pm.

4) Since the electronegativity of O, C and S are different, OCS is polar ⇒ the bond dipole of CO > bond dipole of CS.

Final - Question 4 | General Chemistry 1