Question

Choose the shape that matches each of the following descriptions:

Drag the terms on the left to the appropriate blanks on the right. Note: not all terms will be used.

tetrahedral

bent (109∘)

trigonal planar

bent (120∘)

linear

trigonal pyramidal

1. A molecule with a central atom that has four electron groups and two bonded atoms: A molecule with a central atom that has four electron groups and two bonded atoms: _________________

2. A molecule with a central atom that has three electron groups and two bonded atoms: A molecule with a central atom that has three electron groups and two bonded atoms: ____________________

3. A molecule with a central atom that has two electron groups and two bonded atoms: A molecule with a central atom that has two electron groups and two bonded atoms: ___________________

Answer 1

1. bent (109 ^o)

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4 electron groups means sp3 hybridization with tetrahedral shape, but only bonded to two atoms, makes it a bent shape. Two atom at two corners of tetrahedron, and two lone pairs at other two corner, e.g. H2O

2. bent (120 ^o)

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3 electron groups means sp2 hybridization with trigonal planner shape (120 o bond angle between them), but only bonded to two atoms, which make it bent shape. Two atoms will have bent (120 o) shape, third position with lone pairs. e.g SO2.

3. linear

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2 electron groups means sp hybridization, with linear shape, two atoms are bonded, so liner shape retains. E.g CO2