Sunday, February 4, 2007
Acid, Alkali, Neutral

Our theme is Acid, Alkali or Neutral?

SOAP / BUBBLES (alkaline)
Soap is a surfactant used together with water for cleaning and washing. Hence, in this case, your facial cleanser is also a type of soap. Soap is actually manufactured by reacting animal fats with alkali! However, there is an exception. Soap can also be produced by reacting vegetable oil with alkali. This process is called Saponification. Sponification also refers to the process in which fats and tissues in a corpse convert into 'grave wax'. However, it will only take place in the presence of alkali.


H2O (neutral)In general, water is neither acidic nor alkaline! However, in different parts of the world, the groundwater can be slightly acidic or alkaline, depending on the location. Most importantly, after water is being treated, it is safe for consumption. No one can survive without water! Therefore, save the water, save the Earth!


Calamine Lotion (alkaline)A bee stung you? Use Calamine Lotion! The Methanol in this lotion will help neutralize the acidity. Also, it provides a cooling effect so as your hand would not burn after the sting. This is just one of its many uses. It can be used to treat rashes, blisters and even sunburn!

TOOTHPASTE (alkaline)Ever wondered why your mouth becomes clean after brushing? The toothpaste is the answer. It is alkaline. Therefore, it helps to neutralise the acid in your mouth. Besides, it also ensures that your teeth is more resistant to decay and bacteria that may cause cavities.

BATTERIES (alkaline)Batteries are of alkali-based! Today, most household uses alkaline batteries. However, everyone should be careful when handling them as they are prone to leaking potassium hydroxide(alkali!), a caustic agent that may cause respiratory, eye and skin irritation!


ORANGE (acidic)Acid can be found in food too! Orange is a highly acidic food due to its high citrus acid content, however, after being metabolized it will cause urine to become alkaline. Therefore, do bear in mind that orange is good for health! (: You wouldn't want your urine to be acidic!


Critic Acid as an ingredient in lemon tea (acidic)5% Citric Acid is present in lemon, giving it a pH between 2 to 3. Hence, this gives lemon an infinite number of uses as it is a cheap source of acid. Lemon juice is sprinkled on fish before it is cooked to neutralize the taste of amines found on fishes. If you drink lemon juice, be sure to rinse your mouth to prevent tooth decay!

Done by:
Qiao Wei
Dionis
Charis
Syahid
Mun Ling

Kitchen's Chemistry

Endothermic reaction - Cooking of Egg
Ice Melting - solid to liquid state
Dissloving - Milo powder in warm water
Diffusion -Green food colouring with water
Different density of liquid
Oxidation taking place

Effervesence - Mentos in RootBeer

Friday, February 2, 2007
Colours

The theme of our set of photographs is Colours.



The Rainbow Colours

Red --- Adding Universal indicator to Hydrochloric Acid (HCl).
Orange --- Potassium Dichromate (K2CR2O7).
Yellow --- Iron(II) Chloride (FeCl2.
Green --- Adding distilled water to Universal indicator.
Blue --- Copper(II) Sulphate (CuSO4.
Indigo --- Concentrated Potassium Permanganate (KMnO4).
Violet --- Adding distilled water to Potassium Permanganate (KMnO4).



Diffusion of colours

The colourless liquid in the beaker is water while the purple is Concentrated Potassium Permanganate (KMnO4). The rate of diffusion is slow due to the high concentration of KMnO4.



Colours of Salts

Starting from left, clockwise:
Orange: Potasium Dichromate K2Cr2O7
White: Sodium Carbonate Na2CO3
Yellow: Potassium Chromate K2CrO4
Black: Potassium Manganate (VII) KMnO4
Light Blue: Copper Sulphate CuSO4.5H2O
Blue Green: Iron(II) Sulphate FeSO4.7H2O
Grey: Manganese Dioxide MnO2
Light Yellow: Sulphur powder
Greenish Blue: Copper(II) Acetate Cu(CH3COO)2.H20
Very Light Green: Copper(II) Carbonate CuCO3
Maroon: Cobalt Chloride CoCl2.6H2O
Blue: Copper(II) Nitrate Cu(NO3)2 . 2.5 H20



Graffiti

The yellow is Lead(II) Iodide, against the black top of our secondary school's Chemistry Lab table.



Layers of Ppt

Yellow: Lead(II) Iodide.
White: Barium Hydroxide.
Blue ppt: Copper(II) Hydroxide.
Light blue solution: Copper(II) Sulphate.
Dark blue solution: Complex ion.



Brown Fumes

This is concocted by adding Concentrated Nitric Acid to copper foil. Nitrogen Dioxide is produced.



Colours of Chromatography

Solvent used: Ethanol.

Group members: Gillian, Chunying, Layjia, Meigui.
Many thanks to our secondary school, Anderson Secondary, for providing the facilities and the chemicals and Miss Patricia Goh, for her unremitting help rendered to us even though we've graduated from the school.