water

Question 1

Whys water a liquid at room temperature?

Answer 1

• Due to making and breaking hydrogen bonds continuously.
• The hydrogen bonds make it difficult for the molecules to escape to form a gas.

Question 2

What’s an advantage of water being a liquid at room temperature?

Answer 2

• Habitat for aquatic organisms.
• Most cellular reactions take place at room temperature so helps organisms survive.

Question 3

How is water a good solvent?

Answer 3

• Due to water being polar anything that is polar or an ion can dissolve in it.

Question 4

Why is it an advantage that water is a good solvent?

Answer 4

• Cellular reactions all take place in solution.
• In humans, important ions can dissolve in the water in blood and then be transported around the body.

Question 5

How is water less dense when it is solid?

Answer 5

• Water molecules in ice are held further apart because each water molecules forms 4 hydrogen bonds to water molecules, making spaced out lattice structure, so it floats.

Question 6

What’s an advantage of water being less dense when solid?

Answer 6

• Creates habitats for aquatic creatures.

Question 7

What is cohesion?

Answer 7

Force of attraction between molecules of the same type.

Question 8

What is an advantage of cohesion?

Answer 8

-Helps water to flow as one mass, which makes it useful for transporting substances.
- Useful in plants, where water has to move all the way up the stems to the leaves.

Question 9

What is adhesion?

Answer 9

Force of attraction between water and different substances.

Question 10

How’s adhesion helpful?

Answer 10

-Helpful as water molecules can move upwards on the sides of xylem vessels.

Question 11

How is surface tension caused?

Answer 11

-Cohesion forces.
- The surface of water contracts, giving it ability to resist force.

Question 12

How is surface tension useful?

Answer 12

• Useful to living organisms, as it allows little animals to walk on water.

Question 13

How does water have a high specific heat capacity?

Answer 13

The hydrogen bonds between water molecules can absorb a lot of energy.

Question 14

Why is water having a high specific heat capacity an advantage?

Answer 14

• It makes a good habitat - the temperature under water is likely to be more stable, than on land.
• Water provides a fairly stable temperature for enzyme-controlled reactions in prokaryotic and eukaryotic cells.

Question 15

How does water have a high latent heat of evaporation?

Answer 15

• It takes a lot of energy to break hydrogen bonds between water molecules.

Question 16

What’s an advantage of water having a high latent heat of evaporation?

Answer 16

• Makes water good at cooling things.
• Mammals sweat when too hot - sweat evaporates and cools down surface of skin.