I don't really have much problem with learning Science as most concepts are pretty easy to digest and remember but its just that I am unable to answer questions in the way markers want me too. To solve the problem I usually try and memorise the types of questions there are and the format for answering them. Occasionally I will have problems memorising certain stuff (e.g. deci, deca, periodic table) and will sometimes have some facts slip my mind but those occur rather randomly and are rather easy to get over.
2. What are the Scientific concepts that you have learnt? (State three examples)
1. Temperature is a measure of the kinetic energy in a specific body.
2. Kinetic Particle Theory tells us that all particles are in continuous and random motion.
3. Liquids and gases diffuse from an area of higher concentration to lower concentration.
3. How are these knowledge and skills useful and relevant to the real world?
It allows me to better understand scientific phenomenon going around me in the real world and helps me understand how certain things work or why they work this way.
4. What have I learnt that which is beyond my textbook/notes knowledge? (List at least 3 examples)
I have learnt about how to heat alcohol without making it combust, what is the factor that causes it to combust, and other ways to heat it up which reduce the chance of combustion.
I also searched for different materials that absorb oxygen. This is what I found:
"The first patent for an oxygen scavenger used an alkaline solution of pyrogallic acid in an air-tight vessel.
Modern scavenger sachets use a mixture of iron powder and sodium chloride.[7] Often activated carbon is also included as it adsorbs some other gases and many organic molecules, further preserving products and removing odors.
When an oxygen absorber is removed from its protective packaging, the moisture in the surrounding atmosphere begins to permeate into the iron particles inside of the absorber sachet. Moisture activates the iron, and it oxidizes to form iron oxide. Typically, there must be at least 65% relative humidity in the surrounding atmosphere before the rusting process can begin. To assist in the process of oxidation, sodium is added to the mixture. Sodium acts as a catalyst, or activator, causing the iron powder to be able to oxidize even with relative low humidity. As oxygen is consumed to form iron oxide the level of oxygen in the surrounding atmosphere is reduced. Absorber technology of this type may reduce the oxygen level in the surrounding atmosphere to below 0.01%.[2][3] Complete oxidation of 1 g of iron can remove 300 cm3 of oxygen in standard conditions. Though other technologies can remove more, iron is the most useful as it does not cause odor like sulfur compounds or passivate like aluminium compounds. Many other alternatives are not food safe.[7] The moisture requirement of iron-based scavengers makes them ineffective in moisture sensitive applications.
The performance of oxygen scavengers is affected by ambient temperature and relative humidity.[8] Newer packaging technologies may use oxygen scavenging polymers to prevent accidental ingestion of oxygen scavengers.[7]"
Taken from http://en.wikipedia.org/wiki/Oxygen_scavenger
From this I could see that there are indeed cheap and common materials that can be used to absorb oxygen even though my teacher and parents told me that such materials may not even exist, and even if they do, would be rare, expensive. This tells me that this is not true. Besides iron, there are also other non-ferrous materials that serve the same purpose, like citrus.I also learnt that the true function of a thistle funnel, unlike what is said in class, is to pour liquids or reagents into narrow neck containers, not to put materials that absorb chemicals as what was said in class. (Mr Tan if you are reading this could you clarify?)
I still don't really see why my method doesn't work. These oxygen scavengers can reduce oxygen levels to below 0.01%, are cheap and are available. Why not feasible?
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