Application Exercise 7

1a) chemical formula : C5H9N3 1b) 1c) 2a) C16H21N3 b) The ethylamine moiety of the antihistamine is able to interact with the histamine receptor competitively and block the site of histamine binding. 3) Drugs that produces a psychological response : Aspirin, Morphine, Estrogen, Amphetamine    Drugs that inhibit growth of substance that cause infection :(Keflex) antibiotics, Penicillin   4a) The herbal supplement manufacturers should be details of the supplement on the packaging. b) The legislation available in Singapore is the HSA […]

Group 43 Blog Post – The Chemistry Of Gasoline

Introduction Gasoline is a fuel that is distilled from the crude oil. Gasoline consists of organic compounds which exists in the form of various structures and include linear and even cyclic structures such as aromatic or alkane cyclic hydrocarbons. While the composition of gasoline may vary, a common gasoline structure is provided below. In the diagram provided, gasoline is depicted to have 8 carbon atoms and 8 hydrogen atoms.The density of gasoline ranges from 0.71 to 0.77kg/m3. Gasoline plays an […]

Application Exercise 6

1. When acetone dissolves the polymer, the gas present in the foaming agent is allowed to evaporate and is removed from the structure. The polymer becomes more compact and denser as the polymer collapses on itself due to the absence of the gas. 2a. Low density polyethylene(LDPE) is made from ethylene and has an increased amount in branched bonds when compared to HDPE. The Branched arrangement of LDPE results in weak intermolecular bonds within LDPE and results in lower tensile […]

Application Exercise 5

1a) The connection between coal-fired plants and poor visibility is such that coal fired plants release huge amounts of water vapour along with the combustion process. Hence, water vapour when cooled in the forest area in the National Park becomes visible as fog, causing the poor visibility. b) The average pH of rain should be neutral at pH = 7. Therefore, since the average rainfall in Mammoth Cave National Park is 10 times more acidic than natural, the difference in […]

Application Exercise 4

1) The two possibilities are water purification tablets and ultra-violet light water purifier. Comparing these two possibilities, both are similar in terms of their cost. Both methods are cost effective where water purification tablets are only sold for an estimated cost of (50 tablets for $6.20) and ultraviolet light water purification only requires the user to replace the lamp and sleeve of the purifier annually. However, both of these methods differ in their effectiveness. For the water purification tablets, it […]

Application Exercise 4

Earth is not cooling rapidly due to the greenhouse effect. When sun’s radiation is incident on the Earth’s surface, some of it is absorbed and some of it is radiated back to the atmosphere. However, some of the leaving radiation is trapped by greenhouse gases such as carbon dioxide, water vapour, and methane, retaining the heat in the Earth’s atmosphere. This phenomenon is called the greenhouse effect which hence explains why the earth isnt cooling rapidly despite more energy leaving the earth’s […]

Application Exercise 3 Answers

1a. Exothermic. When charcoal burns, heat is released, hence its exothermic. 1b. Endothermic. When water molecules evaporate to form water vapour, water vapour contains more energy. Furthermore, the skin feels cool as temperature decreases when water evaporates, hence it is endothermic. 1c. Endothermic. Heat is absorbed when ice melts, forming water molecules in liquid state which contains higher energy. 2. For a good explosion, a large amount of energy should be released. Hence the reaction should be very exothermic. Therefore […]

Ozone Magic

Today’s group based learning was simply brilliant. My team nose-dived into the arcane world of chemistry with regards to the ozone. Learning about this quaint, yet vital for life, layer was intriguing and very fulfilling as an academic pursuit. We learned and debated about the proper name to be adopted for the ozone layer- whether ozone screen should be used instead- and weighed the pros and cons of each option. We then examined a cartoon depiction of the ozone problem exacerbated […]

Ozone depletion

Today’s lesson is about the use of ozone and how its is currently being depleted. In today’s discussion, we discussed about the why it is not feasible for us to create ozone and then ship it up into the stratosphere to curb with the problem of ozone depletion. There are several reasons why this is not feasible. The 1st reason is that this way doesn’t solve the root of the problem. The method is also not feasible because there is […]