Lewis Structures & VSEPR Theory

Question 1

What is the purpose of a Lewis structure?

Answer 1

To show the arrangement of valence electrons in a molecule.

Question 2

What is the VSEPR theory used for?

Answer 2

Predicting molecular shapes based on electron repulsion.

Question 3

What shape does a molecule with two bonding pairs and no lone pairs have?

Answer 3

Linear.

Question 4

What shape does a molecule with four bonding pairs have?

Answer 4

Tetrahedral.

Question 5

What causes a bent molecular shape?

Answer 5

Lone pairs on the central atom repelling bonded pairs.

Question 6

How do lone pairs affect bond angles?

Answer 6

They decrease bond angles by repelling bonded atoms more strongly.

Question 7

What is the shape of CO2?

Answer 7

Linear.

Question 8

How do multiple bonds affect molecular shape?

Answer 8

They contribute to electron domains but do not always change geometry.

Question 9

What is the molecular shape of NH3?

Answer 9

Trigonal pyramidal.

Question 10

What molecular shape does H2O have?

Answer 10

Bent.