Abstract: The safety of pool water is reliant on chemical sterilisation, to destroy dangerous pathogens. The most common steriliser is chlorine, in the form of hypochlorite ions (OCl-) and hypochlorous acid (HOCl). However sunlight causes drastic decomposition of these chemicals, thus methods to protect chlorine from sunlight have been created for pools. Some of these include pool covers, or chemical stabilisers which combine with the free hypochlorite ions to reduce decomposition. The most common stabiliser is isocyanuric acid ((CONH)3), added until a concentration of 50mg/L is reached. An experiment was devised to test whether the pool cover or the stabiliser would be more effective at retaining chlorine concentrations, however the results …show more content…
For a pool to be safe and comfortable to swim in the pH cannot be too acidic or basic, as both acids and bases are corrosive. The ideal pH for a pool is between 7 and 7.6, with a lower pH causing eye irritation, and a higher pH causing skin rashes (Victoria State Government, 2017). Pool chlorine levels can be difficult to maintain as both OCl- and HOCl are subject to rapid decomposition under UV rays from sunlight (photolysis), and a high exposure day can reduce chlorination by up to 90 percent in just two hours. The chemical decomposition for both free chlorines are demonstrated in reactions 2 and 3 (Becker, 2018). There are multiple methods used to stop the effects of sunlight, one such being chlorine stabilisers. The most common stabiliser is isocyanuric acid ((CONH)3) which bonds with the hypochlorite ions to form dichloroisocyanuric acid (C3O3N3Cl2H), which is stabilised chlorine (reaction 4) (Smith, et al., …show more content…
Since there is no light causing photolysis the chlorine should remain unaffected and undergo a slow ‘natural’ decomposition over time. Contrary to this, the light sample should have the highest chlorine loss, as there is no protection at all and the chlorine is under constant exposure to UV light, hence the highest rate of decomposition. The cover and stabiliser samples should fall between these two extremes, and over all the chlorine concentration of all samples should decrease. The pH of all samples should trend toward 7, as the NaOCl causes higher alkalinity, and as it breaks down and the chlorine is decomposed, it should decrease to approach the pH of water. However, since the (CNOH)3 is an acid, it would be expected that the pH drops significantly after adding, before the rate of pH decrease stabilises and becomes more
Data table 1 Well plate Contents Glucose concentration A 3 drops 5% sucrose + 3 drops distilled water Negative B 3 drops milk+3 drops distilled water Negative C 3 drops 5% sucrose +3 drops lactase Negative D 3 drops milk +3 drops lactase 15+ E 3 drops 20% glucose +3 drops distilled water 110 ++ Questions B. In this exercise, five reactions were performed. Of those reactions, two were negative controls and one was a positive control.
The ozone layer is the one that protects living things from the pure ultraviolet rays of the sun.
One of the most primitive actions known is the consumption of lactose, (milk), from the mother after birth. Mammals have an innate predisposition towards this consumption, as it is their main source of energy. Most mammals lose the ability to digest lactose shortly after their birth. The ability to digest lactose is determined by the presence of an enzyme called lactase, which is found in the lining of the small intestine. An enzyme is a small molecule or group of molecules that act as a catalyst (catalyst being defined as a molecule that binds to the original reactant and lowers the amount of energy needed to break apart the original molecule to obtain energy) in breaking apart the lactose molecule. In mammals, the lactase enzyme is present
DPIP will be used to determine the rate at which the cholorplasts are being reduced. The spectrophotometer will establish the wavelength of light that penitrats the chloroplast solution in turn determining the amount of electrons reduced. In the dark reactions, the spectrophotometer will measure the amount of light passing through a darker solution of DPIP and chloroplasts. In the light reactions, the lighter solution, caused by reduction of the chloroplasts, will allow a larger amount of light to pass through to the photocell of the spectrophotometer. Thus, the spectrophotometer will prove wheter the light or dark reactions affect the rate of photosynthesis in chloroplasts. We will also be using a reference solution made of water, phosphate buffer, and active chloroplasts. The purpose of this solution will be used to set the transmittance level for the experiment. The control solution, which is different than the reference solution, is comprised of water, phosphate buffer, and DPIP. It will be used to prove that the three element of the solution do affect the results- it is strictly the chloroplasts that are subjected to the light/dark conditions.
One of the most effective ways is to wear sunscreen when out in the sun. Sunscreens are designed to protect against sunburn (UVB rays) and generally provide little protection against UVA rays. There are two types of sunscreens, chemical and physical. Chemical sunscreens contain chemicals such as benzophenone or oxybenzone as the active ingredient.
Chlorine is the most common chemical used to treat and sterilize swimming pool water. When chlorine (in the chemical form of calcium hypochlorite) is added to a swimming pool it destroys pathogens and oxidizes materials such as chloramines. When chlorine is added to water a week acid called hypochlorous acid (HOCL) and chloride ions (CL-) are produced. The hypochlorous acid is what gives water the ability to oxidize and sterilize and disinfect the water.
This experiment tested whether or not baking soda affected the rate of photosynthesis over time. For this experiment there was a beaker containing 100ML of running distilled water added to a beaker with 1% or 1 gram of baking soda. Then another beaker was placed beside that beaker with 100ML of 0.2% sodium bicarbonate. This was done to test the rate of photosynthesis with different amounts of baking soda over time. Both beakers were placed under a red light with 25 watts of electricity for two trials at 23 degrees Celsius. After 10 minutes in the first trial, it showed 1% of baking soda caused a greater amount of leaves to float over time; while the 0.2% sodium bicarbonate caused a fewer amount of leaves to float to the top of the beaker overtime.
The advantages of swimming indoors are numerous compared to swimming outdoors for students who currently are enrolled at EFC or staff who are employed by EFC. Swimming in an indoor pool will help to avoid hazardous weather and for students/staff to avoid potential allergies as well. Throughout Earth’s atmosphere, the weather can change abruptly and without warning. When a student or staff member of EFC needs to swim in a pool for exercise and/or leisure, the only option available to them at EFC is the outdoor pool. This pool is susceptible to many types of weather conditions such as rain, snow, sleet, hail, and freezing winds and temperatures which can freeze or render an outdoor pool unusable. If a small building with an indoor pool inside was built instead of the outdoor pool, anyone attending or employed at EFC could swim all year long whenever t...
Photosynthetic organisms have the ability to convert solar energy into electrochemical energy. This creates a dynamic relationship between the organisms and the light that they absorb. Although light is required to drive photosynthesis, the photosynthetic machinery can only tolerate so much of it. Excess light may lead to the generation of reactive oxygen intermediates resulting in oxidative damage to the photosynthetic apparatus (Niyogi, 1999). Therefore it is necessary for organisms such as the green algae Chlamydomonas reinhardtii to employ photoprotective mechanisms in order to maintain photosynthetic efficiency and reduce stress caused by excess light.
Summer weather is in full swing, which means it’s time to go swimming. Swimming pools can be a lot of fun, but they also require routine maintenance to stay looking great throughout the season.
3.) What type of chlorophyll does the reaction center contain? What are the roles of the other pigments?
...ch are highly resistant to traditional disinfection practices. Moreover, disinfectants themselves can react with the naturally-occuring materials in the water to form byproducts, such as trihalomethanes and haloacetic acids, which can be harmful to human health. Thus, while provide protection from pathogen and microbial, this stage also minimizing the population from disinfection byproduct to reduce the health risks. So, the disinfection byproducts have their own regulation control that requires water systems to use treatment methods to reduce the formation of disinfection byproducts and to meet their own standards requirements so that the water is safe from waterborne pathogens and the potential harmful effects of disinfection byproducts. This is how the water had been treated and it is distributed to human settlements and industrial area for further usage.
Nowadays, water quality becomes an increasingly important problem and draws more and more public’s attention. Water quality is used to define the chemical, biological, and physical characteristics of water (Diersing, 2009). It is a measure of the water condition relative to the requirements of one or more species and to any human need or purpose such as drinking, swimming, and fishing (Johnson et al., 1997). Degradation of water quality through different channels in different sources and different monitoring methods have been widely considered. This literature review seeks to address the factors that determine the water quality. The following factors are the main factors that influence the water quality: concentrations of nutrients nitrogen and phosphorus, concentration of dissolved oxygen, levels of fecal coliform bacteria from human and animal wastes, temperature of water, and sedimentation.
The RNAO states “World Health Organization data suggests that environmental factors account for 24 per cent of the world’s burden of disease and 23 per cent of all deaths” (2012). Environmental determinants of health is mainly centered on whether not the area has clean air and water. This is because air and water are used in every person’s daily life, and if these are contaminated, the health of these persons can be compromised. According to the United States Environmental Protection Agency, the records dating back from 2005 show that the water is safe for all persons, with no pollutants causing illnesses or diseases (Air System Facilities, 2015). In addition, the agency tested the water to see if it had any abnormal microbial levels. In the area there were no disinfectants or pollutants compromising the water. To further determine the environmental determinants, the air was also researched. Today, on September 11, 2015 the UV index was considered to be very high. The agency states “Protection against sun damage is needed” (UV Index, 2015). Since the UV index ranked to be in the very high category, people in this area need to take caution and were sun screen if outdoors. It is recommended that people stay in cool, air conditioned facilities between 1 pm and 4 pm. To continue, the AFS showed that there are no facilities producing air emissions (Air System Facilities, 2015). When there are no facilities producing air
The water in pools has to be disinfected to make it safe for swimming. But the disinfectants added to pools aren’t just killing harmful microbes. They’re also reacting with organic matter in the water to form unwanted disinfection by-products. Most of the precursors to those by-products are brought into the water by swimmers themselves.