- While hiking, you can purify your water via boiling. The basic rule is to make sure you bring the water to a rolling boil for 1 minute at lower altitudes and 3 minutes at altitudes above 2000 meters. Boiling will eliminate bacteria, protozoa, and even viruses. The downside is you’ll use up your cooking fuel and will need to wait for the water to cool down. Another method is to use Chemical Purification via tablets. These tablets dissolve in your water to purify it while weighing almost nothing and are small enough to keep in any pouch for convenience. Traditionally hikers used iodine tablets, but iodine wasn’t able to eliminate Cryptosporidium and also left the water yellow and tasting funky. Today hikers prefer Chlorine Dioxide Tablets, which purify water with a highly active form of oxygen as they dissolve. The downside is needing to wait 30 minutes for the tablets to effectively neutralize Giardia and up to 4 hours when Cryptosporidium is a concern. Lastly, a filtration solution and device can be used. These filter out bacteria and protozoa via microscopic pores in the filter media usually 0.2 microns or smaller, but do not eliminate viruses. Overall, the cheapest would be boiling but it is time consuming and not as efficient as the more costly tablets or filtration system.
The method that is most similar to the methods used in purification of municipal water is filtration where large amounts of water can go through membrane filtration. The filtration of municipal water is far more complicated though, with many steps and types of membranes used to filter out different kinds of impurities like sediments, ions or dissolved substances. These stages may vary depending on what the water is going to be used for (e.g drinking/ lab usage) Comparing to this, the filtration during hiking would be considered very basic and on-the-go.
2. Desalination techniques are not used more widely because its plants and processes are expensive. Also, the process of desalination requires a lot of energy. The same amount of energy can be invested into producing other more important things. Other than that, the brine removed from the desalination process may pollute the surrounding environment and kill the wildlife and vegetation found there.
- The likely major source of the lead in the drinking water is from the water pipes that may have contained some lead components.
No. Improper handling of aqueous chemical waste may cause the leaks to the drinking water but most labs don’t dump toxic compounds such as lead into the sinks but into a waste treatment system. Measures such as reminders for students to make sure no unwanted chemicals will leave the lab and contaminate the water has been used.
4. Water-soluble vitamin includes vitamins B and C. They are considered as polar compounds because they have predominance of polar groups (hydroxyl groups) than non-polar groups (hydrocarbon regions). In addition, according to general rule of thumb, “like dissolves like”. In other words, polar molecule will combine with other polar molecule to form solution. Therefore, water-soluble vitamin is considered as polar molecule, as it can dissolve in water, which is a polar molecule with non-zero net polarity. Fat-soluble vitamin includes vitamin A, D, E and K. They are considered as non-polar compounds because they have predominance of non-polar groups (hydrocarbon regions) than polar groups (hydroxyl groups). Following the same rule of “like dissolves like”, non-polar molecule will combine with other non-polar molecule to form solution. Therefore, fat-soluble vitamin is considered as non-polar molecule, as it can dissolve in fat or lipid, which are non-polar molecules having large regions of non-polar hydrocarbon.