Water Pollution Project (Gracia, Nicole, Kimberley, JiaYu)

Research:

• Water Pollution

Hypothesis:

• The seawater at East Coast Beach is polluted and is acidic.

What we need to find out:

• clarity of seawater
• whether the seawater is acidic or alkaline
• type of dirt particles or rubbish in the seawater
• photographs of evidences of polluted water

Methodology:

1. Walk along East Coach Beach and identify 4 points along the sea with different activities going on.
2. Collect a sample (1 bottle) of seawater at the 4 different locations.
3. Label point A, B, C or D on the bottles.
4. Pour out 2 beakers of 50cm3 of seawater from each sample.
5. Observe the clarity of the seawater and smell it. Record down observations.
6. Pour out some seawater from each sample into different test tubes.
7. Dip red litmus paper and blue litmus paper into the seawater in each test tube then record observations.
8. Drop pH paper into the test tube and record the pH.
9. Filter one of the 2 beakers of seawater from each sample then boil in an evaporating dish until salt is left. Record observations and time.
10. With the other beaker left, boil it straight in an evaporating dish without filtering until salt is left. Record observations and time.
11. Compare the results for the different samples.

Findings:
Bottle A- breakwall (camping, more human activities going on, No rubbish on shore)
Bottle B- control (no human activities, more birds, No rubbish on shore)
Bottle C- left side of jetty (a lot of rubbish on shore, strong waves, washed-up seaweed, fishing)
Bottle D- right side of jetty (No rubbish on shore, small waves)

Smell
A- no smell
B- no smell
C- strong fishy smell
D- mild fishy smell

Clarity (1)least clear----(4)clearest
A- (3)
B- (4)
C- (2)
D- (1)

pH
The seawater samples all turned blue when we dropped pH paper into them. Thus, all of the samples have a pH around 8-9.

Litmus paper test:
All the seawater samples turned the red litmus paper blue but for the blue litmus paper, the colour remained unchanged.

Residue/salt (1)most----(4)least
A- (1)
B- (2)
C- (3)
D- (4)

Salt crystal amount for unfiltered seawater (1)most----(4)least
A- (3)
B- (2)
C- (4)
D- (1)

Time taken for water to evaporate (filtered)
A- 11.55 min
B- 10.57 min
C- 13.09 min
D- 12.33 min

Time taken for water to evaporate (unfiltered)
A- 15.11 min
B- 12.58 min
C- 18.05 min
D- 10.54 min

Conclusion:
We found out that seawater is alkaline with a pH of about 8-9 instead of acidic as mentioned in our hypothesis and that the seawater at East Coast beach is polluted because of the photo evidences of rocks and break walls that have eroded/corroded slightly. It is polluted because overall, unfiltered seawater takes longer to evaporate, meaning that it is less pure than filtered seawater that takes a faster time to evaporate. This proves that the original seawater samples collected had more impurities in it.