SnE Club
Science & Environment, Save the World
Tampines Junior College
2009 Archives
- Conservation Talk at NUS on Wednesday, 11 February 2009
- Background
(A) Trends/Data
- Congo, Brazil and Indonesia are the 3 countries with the highest emission rates. They should not be blamed entirely though due to their agriculture practices that will contribute to those high rates (eg. Methane gas)
- Average world temperature has risen by 0.74 degree Celsius it is expected to rise by 0.2 per decade. This is a significant value in the long run.
(B) Consequences
- Results in heat wave, causing drought and more people to fall sick. Rise of sea level, this may lead to state failure due to massive migration and competition for scarce resources.
(C) Opportunities
- New jobs based on green technology and clean technology can be created.
- Countries have to invest more in research and development (twice the amount by 2012) in order to meet with challenges ahead.
- What we can do
- Individual
- Start from small actions that have huge significance. For instance, sorting out of rubbish before disposal.
- National
- Countries should not hold back environment plans due to the current economic meltdown.
-
Developed countries should contribute more to combat the problem of environmental degradation.
- Interesting Points
High prices of oil is advantageous to the environment as it discourages people to use less fuel, thus reducing emissions level.
- Conclusion
All countries have a part to play in saving our environment. Individuals will also need to play their part to facilitate the plans of the government. At such, the world will be a unified force to fight against the impact of climate change.
Credits to Kokseng
- Experiments
- Magic Milk
A colourful milk experiment. The milk was first poured into a shallow pan, then food colouring was put in drop by drop, creating a colourfully dotted milk. Then, drops of soapy water are dripped into the pan. What happened was that the soap molecules in the water repelled the fat molecules in the milk and in the mean time, the fat molecules are carrying the molecules of dye. Hence the colours were mixed. To put it simply, the colours swirled around and mixed, creating a myriad of colours. Soap works by repelling fat of whatever you are cleaning.
- Speedboat Matchstick
It's supposed to work as the soap breaks the surface tension of the water. The surface tension of the water breaks down as an "oily film rushes across the surface of the water" sending the matchstick "zooming" away. What everyone saw that day was a few geriatric matchsticks making their way across the surface of the water. The speed was described by one "as fast as a couple of arthritic tortoises racing each other". We still have no idea what went wrong. Maybe the water has been contaminated with soap or something.
For the other part of the experiment, a sugar cube is lowered into the bowl and the matches are seen floating towards it. This is because the sugar is porous and sucks water inwards, pulling the matches towards it.
- Lava Lamp
Are you interested in how the lava lamp works? If you do, you can't miss this simple but fun experiment! This experiment will only require a few basic things (A glass jar, Vegetable oil, Salt, Water & Food colouring) found in your house before you start making you very own simple version of Lava Lamp!
Both Lava lamp and this homemade lava lamp make use of the same principle, the difference in density of fluids. 2 immiscible liquids must be used for this to work. In our experiment, salt will slowly dissolve as it travel down the jar taking a blob of oil with it and when it is completely dissolved, the oil will float back up as it is lighter than water.
The lava lamp works slightly differently. The "lava" in the lava lamp is slightly denser than the liquid inside. When it is turned on, the heater in the bottom of the lamp will start to heat up, expanding the "lava" and decreasing its density until it is light enough to float up the liquid! When the "lava" reaches the top, it cools down and sinks towards the bottom.
- Cool Gooey Ooze
The last experiment, as the name suggested "gooey", is a messy experiment, however it is very easy to carry out. You only need cornstarch and water, or if you want it to look cooler, add a few drops of your favourite colour of food colouring! Mix the goo until it feels like liquid when touch and try squeezing it. Surprised? The "solution" was all hard and solid! You can even squeeze and throw the lump of solidify goo at your friend without dirtying the clothes!
This experiment demonstrates iso-tropy properties of certain fluid mixtures. Isotropy is the property of a fluid to become firm when agitated, which is similar to the wet sand on the beaches. If you run on the wet sand on the beach it will be hard and solid, however if you walked slowly, you will sink slightly in.
- Coke and Mentos Experiment
First, we got to understand that the mentos surface is covered with numerous microscopic pits. This applies only for the mint flavored one. The fruits one are covered with a layer of sugar glaze.
Second, the CO2 that is in the Coke is unstable. It will bubble out easily if there is any form of agitation or a nucleation site is provided.
A nucleation site is an area where the CO2 bubbles can form. It normally occurs as a scratch on a smooth surface. The microscopic pits on the surface of the mentos serves as the nucleation sites.
When a mentos is dropped into the coke, the initial agitation from the drop itself creates a few bubbles which kick starts the chain reaction of bubbles forming at the pits of the mentos. Due to the large amounts of pits on the surface of the mentos, a lot of bubbles are formed simultaneously. These bubbles come together and escape from the bottle, carrying a bit of liquid with it. Thus we see the 'fountain' of Coke.
The same effect can be seen, but to a more docile extent, is when you pour a carbonated drink into a glass or plastic cup. In a short time, you can see bubbles clinging onto the surface of the container and straw if there is one. This is also the reason why the Coke froth up when you add salt to it.
There are a few theories out there, and this is one of them. Some may argue that it is a chemical reaction between the Coke and the Mentos, but no. It is a simple mechanical action. The chemicals will create better conditions for the nucleation to take place but it does not affect it chemically.
Content is © Science & Environment Club 2009
- Conservation Talk at NUS on Wednesday, 11 February 2009
- Background
- Congo, Brazil and Indonesia are the 3 countries with the highest emission rates. They should not be blamed entirely though due to their agriculture practices that will contribute to those high rates (eg. Methane gas)
- Average world temperature has risen by 0.74 degree Celsius it is expected to rise by 0.2 per decade. This is a significant value in the long run.
- Results in heat wave, causing drought and more people to fall sick. Rise of sea level, this may lead to state failure due to massive migration and competition for scarce resources.
- New jobs based on green technology and clean technology can be created.
- Countries have to invest more in research and development (twice the amount by 2012) in order to meet with challenges ahead.
(A) Trends/Data
(B) Consequences
(C) Opportunities
- What we can do
- Individual
- Start from small actions that have huge significance. For instance, sorting out of rubbish before disposal.
- National
- Countries should not hold back environment plans due to the current economic meltdown.
-
Developed countries should contribute more to combat the problem of environmental degradation.
- Individual
- Interesting Points
High prices of oil is advantageous to the environment as it discourages people to use less fuel, thus reducing emissions level.
- Conclusion
All countries have a part to play in saving our environment. Individuals will also need to play their part to facilitate the plans of the government. At such, the world will be a unified force to fight against the impact of climate change.
Credits to Kokseng
- Background
- Experiments
- Magic Milk
A colourful milk experiment. The milk was first poured into a shallow pan, then food colouring was put in drop by drop, creating a colourfully dotted milk. Then, drops of soapy water are dripped into the pan. What happened was that the soap molecules in the water repelled the fat molecules in the milk and in the mean time, the fat molecules are carrying the molecules of dye. Hence the colours were mixed. To put it simply, the colours swirled around and mixed, creating a myriad of colours. Soap works by repelling fat of whatever you are cleaning.
- Speedboat Matchstick
It's supposed to work as the soap breaks the surface tension of the water. The surface tension of the water breaks down as an "oily film rushes across the surface of the water" sending the matchstick "zooming" away. What everyone saw that day was a few geriatric matchsticks making their way across the surface of the water. The speed was described by one "as fast as a couple of arthritic tortoises racing each other". We still have no idea what went wrong. Maybe the water has been contaminated with soap or something.
For the other part of the experiment, a sugar cube is lowered into the bowl and the matches are seen floating towards it. This is because the sugar is porous and sucks water inwards, pulling the matches towards it. - Lava Lamp
Are you interested in how the lava lamp works? If you do, you can't miss this simple but fun experiment! This experiment will only require a few basic things (A glass jar, Vegetable oil, Salt, Water & Food colouring) found in your house before you start making you very own simple version of Lava Lamp!
Both Lava lamp and this homemade lava lamp make use of the same principle, the difference in density of fluids. 2 immiscible liquids must be used for this to work. In our experiment, salt will slowly dissolve as it travel down the jar taking a blob of oil with it and when it is completely dissolved, the oil will float back up as it is lighter than water.
The lava lamp works slightly differently. The "lava" in the lava lamp is slightly denser than the liquid inside. When it is turned on, the heater in the bottom of the lamp will start to heat up, expanding the "lava" and decreasing its density until it is light enough to float up the liquid! When the "lava" reaches the top, it cools down and sinks towards the bottom. - Cool Gooey Ooze
The last experiment, as the name suggested "gooey", is a messy experiment, however it is very easy to carry out. You only need cornstarch and water, or if you want it to look cooler, add a few drops of your favourite colour of food colouring! Mix the goo until it feels like liquid when touch and try squeezing it. Surprised? The "solution" was all hard and solid! You can even squeeze and throw the lump of solidify goo at your friend without dirtying the clothes!
This experiment demonstrates iso-tropy properties of certain fluid mixtures. Isotropy is the property of a fluid to become firm when agitated, which is similar to the wet sand on the beaches. If you run on the wet sand on the beach it will be hard and solid, however if you walked slowly, you will sink slightly in. - Coke and Mentos Experiment
First, we got to understand that the mentos surface is covered with numerous microscopic pits. This applies only for the mint flavored one. The fruits one are covered with a layer of sugar glaze.
Second, the CO2 that is in the Coke is unstable. It will bubble out easily if there is any form of agitation or a nucleation site is provided.
A nucleation site is an area where the CO2 bubbles can form. It normally occurs as a scratch on a smooth surface. The microscopic pits on the surface of the mentos serves as the nucleation sites.
When a mentos is dropped into the coke, the initial agitation from the drop itself creates a few bubbles which kick starts the chain reaction of bubbles forming at the pits of the mentos. Due to the large amounts of pits on the surface of the mentos, a lot of bubbles are formed simultaneously. These bubbles come together and escape from the bottle, carrying a bit of liquid with it. Thus we see the 'fountain' of Coke.The same effect can be seen, but to a more docile extent, is when you pour a carbonated drink into a glass or plastic cup. In a short time, you can see bubbles clinging onto the surface of the container and straw if there is one. This is also the reason why the Coke froth up when you add salt to it.
There are a few theories out there, and this is one of them. Some may argue that it is a chemical reaction between the Coke and the Mentos, but no. It is a simple mechanical action. The chemicals will create better conditions for the nucleation to take place but it does not affect it chemically.
Content is © Science & Environment Club 2009 - Magic Milk