Touch Screens and Gloves don't go well together

If you ever try to use a touch screen with a glove on, it will most likely not work. Why is this so? Well, gloves are poor conductors of electricity. The touch screen requires a closed circuit to function. Our bodies are also conductors, and hence when we use our fingers on the touch screen the circuit closes and the touch screen will work. However, since gloves are poor conductors, the
circuit remains open and the touch screen will not work. This is the same for using a stylus. However, it is possible to modify your gloves simply to be able to wear them while using the touch screen. The link below shows how. It is pretty interesting. Have fun!

http://www.instructables.com/id/Making-A-Glove-Work-With-A-Touch-Screen/

Sources:

http://en.wikipedia.org/wiki/Touchscreen#Capacitive

http://en.wikipedia.org/wiki/IPhone#Screen_and_input

Sticky Ice

Why does ice stick to our fingers when we remove it from the fridge? Well, apparently it is due to humidity in the surrounding air. When the surrounding air is wet and humid, your fingers are more moist and the ice will freeze when it comes into contact with the moisture on your fingers. Fortunately, on dryer days your fingers will not be wet and the ice will not stick.

Cells: An Analogy

This is an analogy of cells using animal cells. You probably may not have heard of some of the organelles.

Body: Earth

System: Continent

Organ: Country

Tissue: State

Cell: City

Cell membrane: City border with guards to monitor people entering and leaving the city

Free Ribosome: Individual shop

Ribosome on Rough Endoplasmic Reticulum (RER): Shop part of a franchise

RER: Franchise Headquarters

Smooth Endoplasmic Reticulum (SER): Recycling Plant

Vesicle pinched from RER: Transport vans for shop products

Vesicle pinched from SER: Transport vans for recycled products

Golgi Apparatus: Factory for processing, refining and modifying imported products

Vesicle fusing with Golgi Apparatus: Transport vans arriving and unloading goods

Vesicle pinching off from Golgi Apparatus: Transport vans with ready-to-go goods

Vesicle fusing with cell membrane: Transport vans unloading goods for export out of city

Cytoplasm: Free land

Nucleus: Government

Chromatins: High post officials

Centriole: Civil servants

Nucleolus: President/Prime Minister

Vacuole: Storage Plant

Mitochondria: Power Plant

If you happen to find that my analogy is incorrect at some parts, please let me know so I can change it. Thanks!

Between Chem and Bio

These are some pics of cells. These diagrams contain the different parts of cells and the less known organelles.

Crystallisation

Here is an interesting video explaining crystallisation. It is a silent video but the images speak for it.

Separating Mixtures

Here are some ways to separate the following mixtures:



1) A mixture of non-magnetic materials and iron



Method: Use a magnet



2)A mixture of water, a solid that can dissolve in water and a solid that cannot (eg. water, salt and sand)



Method: filter the mixture to remove the sand, then use distillation to separate the salt and the water



3) 2 liquids that do not mix (eg. water and oil)



Method: Slightly more complicated. There is a special machine built to do so. It is called the API oil-water separator. You can find out about it in Wikipedia at this site: http://en.wikipedia.org/wiki/API_oil-water_separator



4) Air and petroleum

This is definitely more difficult... There is a special type of machine that is used. It is big, bulky and complicated. You can see it at these sites:

http://www.onyxnet.co.uk/clients/mastrad/bub.htm

http://www.geneq.com/catalog/en/air_release_petro.html

The aftermath of coke and mentos

Hi people, these are some choice pics from the coke and mentos experiment. Also, here is the wrap-up of our group's experiment.

Group members: Sarah Tay, Rachel Seah, Stella (who, by the way, took all the photos, thanks!) and me

Objective: To find out how the number of Mentos affects the height of the fountain.

Hypothesis: The more mentos put in, the higher the fountain will go.

Items used: Several tubes of mentos, three bottles of 1.5 litre coke, two meter rulers, two measuring cylinders, one of which got jammed, and one poncho that made me look like Little Red Riding Hood.

Procedure: We were supposed to drop in 10, 20 and 30 mentos respectively into each bottle of coke, but for the first one, Sarah only managed to unjam 2 mentos, so the rest were stuck when the explosion occurred.

Secondly, Sarah managed to fit 16 mentos into the measuring cylinder and pour it all in at once. Stella expertly captured a shot of the coke in mid-air.

Finally, we put in 10 mentos at once. Of course, being me, I put the stupid ruler crooked so the reading was inaccurate.

Our final conclusion was that we were correct, but up to a certain point the coke would stop dissolving the mentos and we would need to add more coke instead.

Here are explosion pics of other groups.

Separation of mixtures

How to separate mixtures:

1. Hand Separation

Example: Separating salt and sand

2. Filtration

Example: Sand and Water

3. Distillation

Example: Alcohol and Water

4. Chromatography, for separating different substances to determine whether they are banned substances

5. Etc. There are a whole lot of other techniques but they are too complicated and not required at this level.


http://www.chemteam.info/Matter/SeparationOfMixtures.html

The Elements

The periodic table of elements was thought up in 1869 by the Russian Chemist, Dmitri Mendeleev. They are in this order: 1. Hydrogen 2. Helium 3. Lithium 4. Beryllium 5. Boron 6. Carbon 7. Nitrogen 8. Oxygen 9. Fluorine 10. Neon 11. Sodium 12. Magnesium 13. Aluminium 14. Silicon 15. Phosphorus 16. Sulfur 17. Chlorine 18. Argon 19. Potassium 20. Calcium


















Also, for those who enjoyed Miss Liang's elements song in class today, I am posting a video, probably by the same makers of Li Shan's Newton video as both use Lego.

Bibliography



http://www.flickr.com/photos/dullhunk/2053007240/



http://en.wikipedia.org/wiki/Periodic_table_%28large_version%29



http://en.wikipedia.org/wiki/Periodic_table