1. Mammoth Cove National Park in Kentucky is in close proximity to the coal-fired electric utility plants in the Ohio Valley. Noting this, the National Parks Conservation Association(NPCA) reported that this national park had the poorest visibility of any in the country

a. What is the connection between coal-fired plants and poor visibility?

Coal-fired plants release sulfur dioxide, creating sulfate particles that are responsible  for 60-85% of the poor visibility in the eastern parks.

b. The NPCA reported ‘the average rainfall in Mammoth Cave National Park is 10 times more acidic than natural.’ From this information and that in your text, estimate the pH of rainfall in the park.

Normal rain has a pH range of 5-6. Given pH = -log[H⁺], the pH will be in a range of 4-5 since the national park is 10 times more acidic than the natural rain.

2. Here are examples of what an individual might do to reduce acid rain. For each, explain the connection to producing acid rain.

a. Hand your laundry to dry it

Hanging laundry to dry does not require the use of clothes dryer and thus less energy is required. Reducing the energy usage will decrease the need for the power companies to produce electricity via the burning of coal. This will reduce the production of acidic gases like carbon dioxide or sulfur dioxide which contributes to acidic rain.

b. Walk, bike, or take public transportation to work.

All these alternatives does reduces the usage of gasoline or fuels which in turn reduces the nitrogen monoxide and carbon dioxide emission. These gases contribute to the acidity of the rain

c. Avoid running dishwashers and washing machines with small loads.

Maximising the load of disherwashers and washing machines will reduce the number of run. Cutting down on such heavy power appliances reduces the energy usage which will decrease the need for the power companies to produce electricity via the burning of coal. This will reduce the production of acidic gases like carbon dioxide or sulfur dioxide which contributes to acidic rain.

d. Add additional insulation on hot water heaters and pipes

This is to reduce the heat loss to the surrounding and thus there is no need to constantly re-heat the water. This will reduce the energy usage of the heater which will decrease the need for the power companies to produce more electricity via the burning of coal. This will reduce the production of acidic gases like carbon dioxide or sulfur dioxide which contributes to acidic rain.

e. Buy locally grown produce and locally produced food.

This reduces the need to import food from oversea, cutting down on the air/land/sea transports. This will cut down on the fuel usage which in turn will decrease the acidic gases such as carbon dioxide and nitrogen monoxide being produced.

Fig 1. The effects of the production of acidic gases by man-made actions on the environment¹.

3a. Give names and chemical formulas for five acids and five bases.

For bases,

Sodium hydroxide : NaOH
Ammonium hydroxide : NH₄OH
Calcium hydroxide : Ca(OH)₂
Lithium hydroxide : LiOH
Magnesium hydroxide : Mg(OH)₂

For acids,

Propanoic acid : CH₃CH₂COOH
Acetic acid :  CH₃COOH
Hydrochloric acid : HCl
Sulfuric acid : H₂SO₄
Nitric acid : HNO₃

b. Name 3 observable properties generally associated with acids and bases.

For acids they are sour, react with metal to produce H₂ gas and changes blue litmus paper to red. For bases they are bitter, slippery and changes red litmus paper to blue.

4. The concerns of acid rain vary across the globe. Many countries in North America and Europe have website dealing with acid rain. Either search to locate one (‘Canada, acid rain’) or use these links to websites in Canada, the UK, or Europe. What are the issues in Singapore? Does the acid deposition originate outside or inside the Singapore’s border?

Singapore being a very small country is susceptible to acid deposition orginated from outside of Singapore’s border. Indonesia has consistently been ‘slashing-and-burning’ their forest to make way for agriculture and such actions have generated a large amount of gaseous and particulate pollutant in the atmosphere. The particulate emission produced a plume which travel towards Singapore when the the wind blows in the correct direction. This had resulted in Singapore to have very poor Pollutant Standard Index (PSI) air quality. Such particulates contain very high concentrations of SO₄^2-, NO₃^– and NH₄⁺. Upon raining, it leads to very acidic rain which is detrimental not only for the environment but also for our infrastructure. 

Also, Singapore is unable to stop the forest burning as it is Indonesia’s domestic affairs. This result in a strain diplomatic relationship between the 2 countries and as such the problem cannot be solved. This will result in prolonged acidic rain in Singapore. 

¹-http://isbscienceg9.blogspot.sg/2015/03/acid-rain_6.html