Question

your answer is incorrect.
check the box next to each molecule on the right that has the shape of the model molecule on the left:
model
molecules
(check all that apply)
so₃
so₃²-
h₃o+
bro₃-
none of the above
you can drag the slider to rotate
molecule.

Explanation:

To solve this, we analyze the molecular geometry (shape) of each molecule by determining the number of bonding pairs and lone pairs around the central atom using the VSEPR theory.

Step 1: Analyze the model molecule's shape

The model has a trigonal pyramidal shape (3 bonding groups, 1 lone pair on the central atom, total 4 electron groups: \( AX_3E \) in VSEPR notation).

Step 2: Analyze \( \boldsymbol{SO_3} \)

• Central \( S \): \( 6 \) valence electrons.
• Bonds: \( 3 \) double bonds to \( O \) (each double bond uses \( 2 \) electrons, but for VSEPR, we count bonding regions).
• Electron groups: \( 3 \) bonding, \( 0 \) lone pairs (\( AX_3 \)) → trigonal planar shape. Not matching.

Step 3: Analyze \( \boldsymbol{SO_3^{2-}} \)

• Central \( S \): \( 6 + 2 = 8 \) valence electrons (due to \( 2- \) charge).
• Bonds: \( 3 \) single bonds to \( O \) (each \( O \) has \( 6 \) non - bonding electrons, 1 bond per \( O \)).
• Electron groups: \( 3 \) bonding, \( 1 \) lone pair (\( AX_3E \)) → trigonal pyramidal shape. Matches the model.

Step 4: Analyze \( \boldsymbol{H_3O^+} \)

• Central \( O \): \( 6 - 1 = 5 \) valence electrons (due to \( +1 \) charge).
• Bonds: \( 3 \) single bonds to \( H \).
• Electron groups: \( 3 \) bonding, \( 1 \) lone pair (\( AX_3E \)) → trigonal pyramidal shape. Matches the model.

Step 5: Analyze \( \boldsymbol{BrO_3^-} \)

• Central \( Br \): \( 7 + 1 = 8 \) valence electrons (due to \( -1 \) charge).
• Bonds: \( 3 \) single bonds to \( O \) (each \( O \) has \( 6 \) non - bonding electrons, 1 bond per \( O \)).
• Electron groups: \( 3 \) bonding, \( 1 \) lone pair (\( AX_3E \)) → trigonal pyramidal shape. Matches the model.

Answer:

The molecules with the same shape as the model are \( \boldsymbol{SO_3^{2-}} \), \( \boldsymbol{H_3O^+} \), and \( \boldsymbol{BrO_3^-} \). So we check the boxes next to \( SO_3^{2-} \), \( H_3O^+ \), and \( BrO_3^- \).