Ocean Acidification

Question 1

Co2 from atmosphere dissolves in seawater

2 Equations

Answer 1

1. CO2 (g) ⇌ CO2 (aq)
2. CO2 (aq) + H2O (l) ⇌ H2CO3 (aq)

Question 2

H2CO3 ionises

2 equations

Answer 2

3. H2CO3 (aq) ⇌ H+ + HCO3 -
4. HCO3- ⇌ H+ + CO3 2-

increase in H+ favours reverse in E4. decreasing [CO3 2-]

Question 3

Impact on calcification

1 equation

Answer 3

5. Ca2+ + CO3 2- ⇌ CaCO3(s)

decrease in [CO32-], reverse favoured which decreases [CaCO3]

Question 4

What to use when explaining ocean acidification

Answer 4

LCP

Question 5

impact of ocean acidification

2

Answer 5

• increase [H+] = decrease pH
• decrease [CO3 2-] = decalcification

calcium dissolves

Question 6

Consequences of decalcification of marine shells

4

Answer 6

• increase predation
• decrease population
• disruptions to ecosystem
• reduced biodiversity

Question 7

Societal impacts of ocean acidification

3

Answer 7

• threats to food security & fisheries
• decreased tourism
• impacts on coastal communities & coastal protection