Question

draw all equivalent resonance structures in which the s atom obeys the octet rule for the sulfur trioxide molecule , SO3.

Answer 1

Resonance structures of sulfur trioxide (SO3) in which the sulfur atoms obey the octet rule can be drawn by rearranging the electron distribution while maintaining the same overall connectivity. The resonance structures involve placing the oxygen atoms around the central sulfur atom with single bonds. Lone pairs are distributed to satisfy the octet rule for each oxygen atom by making multiple bonds between sulfur and oxygen, leading to a more stable molecule.

Step-by-step explanation:

Sulfur trioxide (SO3) is a molecule that exhibits resonance. In resonance structures, the atoms are rearranged to show different electron distributions while maintaining the same overall connectivity. To draw the resonance structures, start by placing the oxygen atoms around the central sulfur atom. Each oxygen atom is connected to the sulfur atom via a single bond. Next, distribute the lone pairs to satisfy the octet rule for each oxygen atom. This can be done by making multiple bonds between the sulfur and oxygen atoms. Here are the resonance structures of SO3:

Structure 1:

O= S = O

Structure 2:

O– S = O+

Structure 3:

O+ S – O

These resonance structures indicate that the double bond character in SO3 is spread out over multiple bonds, resulting in a more stable molecule.

Answer 2

To draw equivalent resonance structures for SO3 obeying the octet rule, assign a double bond to each oxygen atom one at a time. The remaining oxygen atoms will have single bonds with sulfur and possess three lone pairs. Sulfur exhibits sp² hybridization, and the overall molecular geometry is trigonal planar.

Step-by-step explanation:

The student's question pertains to drawing the resonance structures for sulfur trioxide (SO3) while adhering to the octet rule. Sulfur trioxide can be represented by several equivalent resonance structures which distribute the double bonds among the three oxygen atoms differently. Each oxygen atom gets a turn at having the double bond with the sulfur atom. According to the octet rule, each atom should have eight electrons in its valence shell, which can be achieved through the sharing of electrons via bonds.

In resonance structures of SO3, sulfur has a total of six valence electrons, which it shares with the three oxygen atoms. However, to comply with the octet rule, we must ensure that only one double bond is present at a time within the structure, allowing sulfur to maintain eight electrons in its valence shell. The creation of multiple resonance structures indicates the delocalization of the pi electrons amongst the sulfur-oxygen bonds.

The less electronegative sulfur is positioned in the center, with oxygen atoms surrounding it. To satisfy the octet rule, the oxygen atoms have lone pairs, and the double bonds are placed in such a way to ensure that all atoms have complete octets. The resonance structures reflect the molecular geometry predicted by VSEPR theory and the sp² hybridization of sulfur, resulting in a trigonal planar shape for each resonance form of SO3.