Mr Jose
Pool Chemistry
Equilibrium system and stress factors
Jake
14/08/2014
Pool Chemistry
Introduction
Pools with crystal clear water look inviting on a hot day however there may be unseen hazards. Invisible dangerous pathogens and microorganisms may be present in pools that aren’t treated properly and can result in harmful side effects like swimmers ear or diarrhoea. Disinfectants are used to treat pools and chlorine is by far the most commonly used. Hypochlorous acid (HOCl) is the substance that sanitises these swimming pools (De La Matter, 2012). If kept within specified pH parameters then the system works well however there are many stressors of the backyard pool system. This includes variations in pH and depletion of hypochlorite ions due to UV exposure. These stress factors can affect the equilibrium systems that take place within a swimming pool.
1. How can pool owners use an understanding of the equilibrium system between the hypochlorite ion and the hypochlorous acid to help maintain their pools?
2. What is the effect of sunlight on …show more content…
The Pk value for this equilibrium system is 6.3. It is evident that the pH is dependent on the concentration of hydrogen carbonate ions (HCO3-) and the concentration of carbon dioxide (CO2) in the air above the pool.
equation 7
For optimal buffering capacity the ph of the pool (recommended to be 7.2 – 7.8) should be kept within one pH of the Pk value of the buffering system (calculated to be 6.3) (Smith, 2006). The buffering system recommended pH range would be between 5.3- 7.3. This is only marginally within the recommended pH range of the pool of 7.2 – 7.8. The 7.3 pH upper limit for the buffer system would be ideal. For the 7.3 pH to be maintained there would have to be sufficient sodium bicarbonate added to the pool to achieve a 10:1 ratio of hydrogen carbonate ions to carbon dioxide as per the equation 8 (Smith, 2006). equation 8
Pool Chemistry
Equilibrium system and stress factors
Jake
14/08/2014
Pool Chemistry
Introduction
Pools with crystal clear water look inviting on a hot day however there may be unseen hazards. Invisible dangerous pathogens and microorganisms may be present in pools that aren’t treated properly and can result in harmful side effects like swimmers ear or diarrhoea. Disinfectants are used to treat pools and chlorine is by far the most commonly used. Hypochlorous acid (HOCl) is the substance that sanitises these swimming pools (De La Matter, 2012). If kept within specified pH parameters then the system works well however there are many stressors of the backyard pool system. This includes variations in pH and depletion of hypochlorite ions due to UV exposure. These stress factors can affect the equilibrium systems that take place within a swimming pool.
1. How can pool owners use an understanding of the equilibrium system between the hypochlorite ion and the hypochlorous acid to help maintain their pools?
2. What is the effect of sunlight on …show more content…
The Pk value for this equilibrium system is 6.3. It is evident that the pH is dependent on the concentration of hydrogen carbonate ions (HCO3-) and the concentration of carbon dioxide (CO2) in the air above the pool.
equation 7
For optimal buffering capacity the ph of the pool (recommended to be 7.2 – 7.8) should be kept within one pH of the Pk value of the buffering system (calculated to be 6.3) (Smith, 2006). The buffering system recommended pH range would be between 5.3- 7.3. This is only marginally within the recommended pH range of the pool of 7.2 – 7.8. The 7.3 pH upper limit for the buffer system would be ideal. For the 7.3 pH to be maintained there would have to be sufficient sodium bicarbonate added to the pool to achieve a 10:1 ratio of hydrogen carbonate ions to carbon dioxide as per the equation 8 (Smith, 2006). equation 8