Intermolecular Forces in Water and Ammonia

The video discusses the difference in boiling points between ammonia (NH3) and water (H2O). Ammonia boils at -33.34°C, while water boils at 100°C. This difference is attributed to hydrogen bonding. Water has two lone pairs, allowing for more hydrogen bonds, resulting in stronger intermolecular forces. This requires more energy to break, leading to a higher boiling point. Ammonia, with only one lone pair, forms fewer hydrogen bonds, making it easier to separate molecules and boil at a lower temperature.

What is the boiling point of ammonia?

• -33.34 degrees Celsius

• 0 degrees Celsius

• 50 degrees Celsius

• 100 degrees Celsius

Why does water have a higher boiling point than ammonia?

• Water has more hydrogen atoms

• Water has two lone pairs allowing more hydrogen bonding

• Ammonia is heavier than water

• Water is denser than ammonia

How many lone pairs does ammonia have?

• None

• One

• Three

• Two

What is the main reason ammonia boils at a lower temperature than water?

• Ammonia has a higher molecular weight

• Ammonia is more volatile

• Ammonia has fewer hydrogen bonds

• Ammonia is less dense

What effect does hydrogen bonding have on water molecules?

• It has no effect

• It strengthens the intermolecular forces

• It weakens the intermolecular forces

• It makes them repel each other

What must be done to break the intermolecular forces in water?

• Decrease the temperature

• Add more water

• Increase the pressure

• Add a lot of energy

How many lone pairs does water have?

• One

• Two

• Three

• Four

What is the main topic discussed by Dr. B?

• The freezing point of water

• The chemical composition of ammonia

• The boiling point difference between ammonia and water

• The density of water and ammonia