Inorganic Ions and Water Research - 29/11/23

Question 1

In a water molecule, where’s the partial positive (δ+) and partial negative (δ-) end on which end?

Answer 1

• The partial positive (δ+) is at the Hydrogen ends
• The partial negative (δ-) is at the Oxygen end

Question 2

Why is water important? [2]

Answer 2

• Water is vital to living organsims
• Makes up about 80% of cell’s contents

Question 3

List the different properties of Water.
[6]

Answer 3

1. It’s a metabolite
2. It’s an important solvent
3. It has a relatively high heat capacity
4. It has a relatively large latent heat of vaporisation
5. It has strong cohesion between water molecules
6. It’s a polar molecule

Question 4

What is the importance of Water being a metabolite?

Answer 4

It can help in metabolic reactions like condensation and hydrolysis reaction

Question 5

What is the importance of Water being a solvent?
[2]

Answer 5

• Allows gas, enzyme and other waste products to readily diffuse
• Where most metabolic reactions take place in solution

Question 6

What is the importance of Water having a relatively high heat capacity?

Answer 6

• Helps minimise temperature fluctuations in living things therefore acts as a buffer

Question 7

How does Water have a relatively high heat capacity?

Answer 7

• Because water molecules stick together with hydrogen bonds it means that a lot of energy is required to break bonds

Question 8

How does Water have a relatively large latent heat of vaporisation?

Answer 8

Because hydrogen bond means that it requires a lot of energy to evaporate 1 gram of water

Question 9

What is the importance of Water having a relatively large latent heat of vaporisation?

Answer 9

Evaporation of water provides a cooling effect with little water loss

Question 10

What is the importance of Water having a strong cohesion between water molecules?
[3]

Answer 10

• Enables effective transport of water in tube like the xylem
• Strong cohesion supports columns of water
• Strong cohesion causes the SA tension at the water-air boundary to be high

Question 11

Give examples of where Inorganic Ions sometimes appear.
[2]

Answer 11

1. Solution in the cytoplasm
2. Body fluids of organisms

Question 12

What are the 4 different inorganic ions in organisms?

Answer 12

1. Iron ion
2. Hydrogen ion
3. Sodium ion
4. Phosphate ion

Question 13

What is the role of Iron ion in the body? [2]

Answer 13

• Component of haemoglobin
• An oxygen carrying molecule in RBC

Question 14

What is the role of Hydrogen ion in the body? [2]

Answer 14

• It determines the pH of substances such as blood
• The higher the concentration of hydrogen ions, the lower the pH

Question 15

What is the role of Sodium ion in the body?

Answer 15

Co-transport of glucose and amino acids

Question 16

What is the role of Phosphate ions in the body?

Answer 16

Component of DNA and ATP

Question 17

What are the properties of Iron ion in the body?

Answer 17

Made up of 4 different polypeptide chains, each with an iron ion in centre