Friday, September 16, 2011
Term 3 reflections
As compared to the previous terms, i have studied comparatively harder for science but still it is not enough when the other subjects are put into comparison. This time, we face Ecology and Refraction. Firstly, i always mess up when it comes to refractions and nextly, ecology is a new topic (although DrTanKK says its a piece a cake if we have learnt our primary school science well). I went forward to focus more and alot on the on the other subjects, trying to actually do well in them and, at the same time, trying to get as many ACE points as possible to not fail terribly for my Independent Studies. THerefore, i did not even start revising until the night before, where i started to revise from around 9 all the way till 4. I should have figured that it wasn't wise, because it triggered my illness to almost explode if i did not take my medicine. When the teacher was giving out the paper, i was beside. All the numbers i saw were mostly 30+/40, so i thought maybe i could be able to get more than 30 too. When i received my paper, i realised how lucky i was - 30.5/40. It was below average for class, even though i scored an A1. As for the EOYs, i have learnt to revise a few days early in case i have any inquiries and question which i do not understand. And of course, not to think that i can make it overnight, especially with this condition of mine going on.
Term 2 reflections
Okay, this term we have some chem and physics, so i thought it was going to be okay since my chemistry foundation was quite strong in term 1, if i remember correctly. Before the term, i believed that i just have to study and take a peek at the periodic table once in a while and i will do fine, which leaves me with physics. As for physics, this term was also extremely easy because, firstly, my dad actually learns physical chemistry, not chemistry, and his best subject all along was physics, thus i know i can always ask him questions when im not sure. Secondly, we are not tested on reFRACtion, but instead on reFLECtion, which makes things a lot easier. Thus i did not really pay much attention to science that term, which turned out to be a fatal mistake, because i actually forgot that we have to know, and remember how to write those equations as well. That hit me right on the day of the test, when i saw my classmates mugging in class, but it was too late. In the end, it became a blockage for me to be scoring higher, luckily for me, the paper one had a faction on equations, which was a close call for me. I guess this sentence will end my reflections for Term 2.
Term 1 reflections
I feel that in Term 1, the term which we learnt on chemistry, the periodic table, ionic bonding and covalent bonding, i was still kind of blur on what to do, how to do, to ace the test, or the term. Therefore, i still stick with the very few basic, obvious steps for studying in a secondary school like listening in class, handing in homework and some revision before the test. But due to the fact that secondary 2 is tougher than secondary 1, i was constantly falling asleep in class and did not really memorize all those hard-to-remember all those annoying elements in the periodic table. I was lucky that both my parents took chemistry as their main subject in university, so they went ahead to correct my when they realised that the elements were not in my head. Therefore, i went through a few days of grueling sessions just to remember almost 2/3 of the periodic table. It was worth it, though.
Enrichment / Research Activities for ACE Qn 4~
Enrichment / Research Activities for ACE
Qn 4~
A. Human activities such as polluting the environment in such or near such forests might cause acid rain into the forest and streams, damaging the habitat for the Ants and Trees to live in, thus making the ants unable to use the tree to attract prey and feed. Humans can also cut down the forests through deforestation and even destroy vast areas of the forest. Humans hiking into the forest might also throw rubbish into the forest and thus pollute the environment, making it unsuitable for the ants to live in.
B. The three different types of symbiotic relationships are firstly, mutualism, between the mould and the ants. The mould helps the ants to ants by growing around the trap built by the ants and reinforcing it. The ants in turn provide a place for the mould to grow without harm, under protection of the ants. The second relationship is the relationship between predator and prey, the ants being the predator and the passers-by of the trap being the prey. The last relationship is parasitism between the trees and the ants. The ants destroy the tree by cutting the hairs of the trees and using it for their purpose, damaging the tree.
Qn 4~
A. Human activities such as polluting the environment in such or near such forests might cause acid rain into the forest and streams, damaging the habitat for the Ants and Trees to live in, thus making the ants unable to use the tree to attract prey and feed. Humans can also cut down the forests through deforestation and even destroy vast areas of the forest. Humans hiking into the forest might also throw rubbish into the forest and thus pollute the environment, making it unsuitable for the ants to live in.
B. The three different types of symbiotic relationships are firstly, mutualism, between the mould and the ants. The mould helps the ants to ants by growing around the trap built by the ants and reinforcing it. The ants in turn provide a place for the mould to grow without harm, under protection of the ants. The second relationship is the relationship between predator and prey, the ants being the predator and the passers-by of the trap being the prey. The last relationship is parasitism between the trees and the ants. The ants destroy the tree by cutting the hairs of the trees and using it for their purpose, damaging the tree.
Enrichment / Research Activities for ACE Qn 2 ~
Enrichment / Research Activities for ACE
Q2 ~
A. Pual Buxman does not approve of the way some farmers just spray insecticide on pests whenever they see them. This is because this method affects and lowers the health standards, shown in Ground-Water tests. Apart from that, the way of just spraying insecticide on the pests produces more fruit losses.
B. This is the usage of natural predators to kill pests instead of pesticides, but it is more labour intensive.
C. With insecticides, the many of the pests are directly killed and therefore there would not be any secondary consumers like spiders, praying mantis, thus creating no food for birds, and birds will leave the area permanently. As for worms, the insecticide leaks into the soil and make it unsuitable for the worm to survive, thus it drives worms away.
D. Organic farming is the form of faming crops and plants that relies on methods, unlike non organic farming which uses certain pesticides, fertilizers or plant growth enhancers, such as crop rotation, green manure. It also biologically controls pests on a farm.
E. It is the balance between the number of pests and their predators such the predators and feed on the pests and not let them destroy the plants yet do not let them die out or the predators they themselves might also die out in that specific area.
F. Broad Spectrum Fertilizers are fertilizers that can fertilize a huge variety of plants or crops and contain a wide supply of micro-nutrients.
Q2 ~
A. Pual Buxman does not approve of the way some farmers just spray insecticide on pests whenever they see them. This is because this method affects and lowers the health standards, shown in Ground-Water tests. Apart from that, the way of just spraying insecticide on the pests produces more fruit losses.
B. This is the usage of natural predators to kill pests instead of pesticides, but it is more labour intensive.
C. With insecticides, the many of the pests are directly killed and therefore there would not be any secondary consumers like spiders, praying mantis, thus creating no food for birds, and birds will leave the area permanently. As for worms, the insecticide leaks into the soil and make it unsuitable for the worm to survive, thus it drives worms away.
D. Organic farming is the form of faming crops and plants that relies on methods, unlike non organic farming which uses certain pesticides, fertilizers or plant growth enhancers, such as crop rotation, green manure. It also biologically controls pests on a farm.
E. It is the balance between the number of pests and their predators such the predators and feed on the pests and not let them destroy the plants yet do not let them die out or the predators they themselves might also die out in that specific area.
F. Broad Spectrum Fertilizers are fertilizers that can fertilize a huge variety of plants or crops and contain a wide supply of micro-nutrients.
The Production and Uses of Sulfuric Acid
Sulfuric acid is a strong mineral acid with the molecular formula H2SO4. Its historical name is vitriol. The salts of sulfuric acid are called sulfates. Sulfuric acid is soluble in water at all concentrations. Sulfuric Acid has many uses worldwide, they include lead-acid batteries for cars and other vehicles, ore processing, fertilizer manufacturing, oil refining and removing rust/oxidation.
A nation's sulfuric acid production is a good indicator of its industrial strength. World production in 2001 was 165 million tons, with an approximate value of US$8 billion. The major use for sulfuric acid is for the production of phosphoric acid which is used for the manufacture of phosphate fertilizers as well astrisodium phosphate for detergents. In this method, phosphate rock is used. Fluor apatite is treated with 93% sulfuric acid to produce calcium sulfate, hydrogen fluoride and phosphoric acid. The hydrogen fluoride is then removed as hydrofluoric acid. The overall process can be represented as:
Ca5F(PO4)3 + 5 H2SO4 + 10 H2O → 5 CaSO4•2 H2O + HF + 3 H3PO4
Sulfuric acid is also used in large quantities by the iron and steelmaking industry to remove oxidation, rust from automobiles and appliances. Used acid is often recycled via a Spent Acid Regeneration (SAR) plant. These plants combust spent acid with natural gas, refinery gas, fuel oil or other fuel sources. This combustion process produces gaseous sulfur dioxide and sulfur trioxide which are then used to manufacture new sulfuric acid. SAR plants are common additions to metal smelting plants, oil refineries, and other industries where sulfuric acid is consumed in bulk, as operating a SAR plant is much cheaper than the recurring costs of spent acid disposal and new acid purchases.
Ammonium sulfate, an important nitrogen fertilizer, is most commonly produced as a byproduct from coking plants supplying the iron and steel making plants. It is produced by reacting the ammonia produced in the thermal decomposition of coal with waste sulfuric acid. This allows the ammonia to be crystallized out as a salt and sold into the agro-chemicals industry.
Another important use for sulfuric acid is for the manufacture of aluminum sulfate, also known as paper maker's alum. This can react with small amounts of soap on paper pulp fibers to give gelatinous aluminum carboxylates, which help to coagulate the pulp fibers into a hard paper surface. It is also used for making aluminum hydroxide, which is used at water treatment plants to filter out impurities, as well as to improve the taste of the water.
Regarding the production of Sulfuric Acid, there are two major processes “lead chamber” and “contact” for production of sulfuric acid, and it is available commercially in a number of grades and concentrations. The lead chamber process, the older of the two processes, is used to produce much of the acid used to make fertilizers as it produces a relatively dilute acid (62%–78% H2SO4). The contact process produces a purer, more concentrated acid but requires purer raw materials and the use of expensive catalysts. In both processes sulfur dioxide is oxidized and dissolved in water. The sulfur dioxide is obtained by burning sulfur, by burning iron sulfides, by roasting nonferrous sulfide ores preparatory to smelting, or by burning hydrogen sulfide gas. Some sulfuric acid is also made from ferrous sulfate waste solutions from pickling iron and steel and from waste acid sludge from oil refineries.
In the lead chamber process, hot sulfur dioxide gas enters the bottom of a reactor called a Glover tower where it is washed with nitrous vitriol and mixed with nitric oxide and nitrogen dioxide gases. Some of the sulfur dioxide is then oxidized to sulfur trioxide and dissolved in the acid wash to form tower acid or Glover acid (about 78% H2SO4). From the Glover tower a mixture of gases (including sulfur dioxide and trioxide, nitrogen oxides, nitrogen, oxygen, and steam) is transferred to a lead-lined chamber where it is reacted with more water. Sulfuric acid is formed by a complex series of reactions; it condenses on the walls and collects on the floor of the chamber. There may be from three to twelve chambers in a series; the gases pass through each in succession. The acid produced in the chambers, often called chamber acid or fertilizer acid, contains 62% to 68% H2SO4. After the gases have passed through the chambers they are passed into a reactor called the Gay-Lussac tower where they are washed with cooled concentrated acid (from the Glover tower); the nitrogen oxides and un reacted sulfur dioxide dissolve in the acid to form the nitrous vitriol used in the Glover tower. Remaining waste gases are usually discharged into the atmosphere.
In the contact process, purified sulfur dioxide and air are mixed, heated to about 450°C, and passed over a catalyst; the sulfur dioxide is oxidized to sulfur trioxide. The sulfur trioxide is cooled and passed through two towers. In the first tower it is washed with Oleum (fuming sulfuric acid, 100% sulfuric acid with sulfur trioxide dissolved in it). In the second tower it is washed with 97% sulfuric acid; 98% sulfuric acid is usually produced in this tower. Waste gases are usually discharged into the atmosphere. Acid of any desired concentration may be produced by mixing or diluting the products of this process.
A nation's sulfuric acid production is a good indicator of its industrial strength. World production in 2001 was 165 million tons, with an approximate value of US$8 billion. The major use for sulfuric acid is for the production of phosphoric acid which is used for the manufacture of phosphate fertilizers as well astrisodium phosphate for detergents. In this method, phosphate rock is used. Fluor apatite is treated with 93% sulfuric acid to produce calcium sulfate, hydrogen fluoride and phosphoric acid. The hydrogen fluoride is then removed as hydrofluoric acid. The overall process can be represented as:
Ca5F(PO4)3 + 5 H2SO4 + 10 H2O → 5 CaSO4•2 H2O + HF + 3 H3PO4
Sulfuric acid is also used in large quantities by the iron and steelmaking industry to remove oxidation, rust from automobiles and appliances. Used acid is often recycled via a Spent Acid Regeneration (SAR) plant. These plants combust spent acid with natural gas, refinery gas, fuel oil or other fuel sources. This combustion process produces gaseous sulfur dioxide and sulfur trioxide which are then used to manufacture new sulfuric acid. SAR plants are common additions to metal smelting plants, oil refineries, and other industries where sulfuric acid is consumed in bulk, as operating a SAR plant is much cheaper than the recurring costs of spent acid disposal and new acid purchases.
Ammonium sulfate, an important nitrogen fertilizer, is most commonly produced as a byproduct from coking plants supplying the iron and steel making plants. It is produced by reacting the ammonia produced in the thermal decomposition of coal with waste sulfuric acid. This allows the ammonia to be crystallized out as a salt and sold into the agro-chemicals industry.
Another important use for sulfuric acid is for the manufacture of aluminum sulfate, also known as paper maker's alum. This can react with small amounts of soap on paper pulp fibers to give gelatinous aluminum carboxylates, which help to coagulate the pulp fibers into a hard paper surface. It is also used for making aluminum hydroxide, which is used at water treatment plants to filter out impurities, as well as to improve the taste of the water.
Regarding the production of Sulfuric Acid, there are two major processes “lead chamber” and “contact” for production of sulfuric acid, and it is available commercially in a number of grades and concentrations. The lead chamber process, the older of the two processes, is used to produce much of the acid used to make fertilizers as it produces a relatively dilute acid (62%–78% H2SO4). The contact process produces a purer, more concentrated acid but requires purer raw materials and the use of expensive catalysts. In both processes sulfur dioxide is oxidized and dissolved in water. The sulfur dioxide is obtained by burning sulfur, by burning iron sulfides, by roasting nonferrous sulfide ores preparatory to smelting, or by burning hydrogen sulfide gas. Some sulfuric acid is also made from ferrous sulfate waste solutions from pickling iron and steel and from waste acid sludge from oil refineries.
In the lead chamber process, hot sulfur dioxide gas enters the bottom of a reactor called a Glover tower where it is washed with nitrous vitriol and mixed with nitric oxide and nitrogen dioxide gases. Some of the sulfur dioxide is then oxidized to sulfur trioxide and dissolved in the acid wash to form tower acid or Glover acid (about 78% H2SO4). From the Glover tower a mixture of gases (including sulfur dioxide and trioxide, nitrogen oxides, nitrogen, oxygen, and steam) is transferred to a lead-lined chamber where it is reacted with more water. Sulfuric acid is formed by a complex series of reactions; it condenses on the walls and collects on the floor of the chamber. There may be from three to twelve chambers in a series; the gases pass through each in succession. The acid produced in the chambers, often called chamber acid or fertilizer acid, contains 62% to 68% H2SO4. After the gases have passed through the chambers they are passed into a reactor called the Gay-Lussac tower where they are washed with cooled concentrated acid (from the Glover tower); the nitrogen oxides and un reacted sulfur dioxide dissolve in the acid to form the nitrous vitriol used in the Glover tower. Remaining waste gases are usually discharged into the atmosphere.
In the contact process, purified sulfur dioxide and air are mixed, heated to about 450°C, and passed over a catalyst; the sulfur dioxide is oxidized to sulfur trioxide. The sulfur trioxide is cooled and passed through two towers. In the first tower it is washed with Oleum (fuming sulfuric acid, 100% sulfuric acid with sulfur trioxide dissolved in it). In the second tower it is washed with 97% sulfuric acid; 98% sulfuric acid is usually produced in this tower. Waste gases are usually discharged into the atmosphere. Acid of any desired concentration may be produced by mixing or diluting the products of this process.
Invention of Science
How was science, "invented"? I believe that since a long time before, science was the result of curiosity. Long ago, when people could not understand something, like what is, and how to start a fire. Out of curiosity or uncertainty, humans would go and find out about what is it, think, and come out with an answer, the theory or law as we call it now. The basic scientific method (if i am not wrong) of coming out with a hypothesis, experimenting and confirming just originated like that. Simply.
Gradually, as more finds out about a certain theory, they educated and teach their children about it to use it for them, not against them. Thus, as far as humans first appeared until now, science accumulated almost like cell division, accumulating as time goes by. As science develops into our current world, it is more than just plainly for the curious ones, it is for everyone who lives in this world. Interacting with science everyday, it has already become something that is pinned fused into our life, way more than how some people cannot "survive" without an Iphone. It is the reason we have electricity, all these gadgets, these medicine, and the reason i am writing this.
Gradually, as more finds out about a certain theory, they educated and teach their children about it to use it for them, not against them. Thus, as far as humans first appeared until now, science accumulated almost like cell division, accumulating as time goes by. As science develops into our current world, it is more than just plainly for the curious ones, it is for everyone who lives in this world. Interacting with science everyday, it has already become something that is pinned fused into our life, way more than how some people cannot "survive" without an Iphone. It is the reason we have electricity, all these gadgets, these medicine, and the reason i am writing this.
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