Cliques

Tuesday, July 30, 2013

Chemical Garden~

Chemical garden~ What is that? Any idea? 


Is it like this?

Keep reading to find out...

Since its a chemical garden, then we should use chemicals...
Chemicals needed:
1. Sodium silicate
2. Magnesium Sulphate
3. Copper (II) Sulphate
4. Copper (II) Nitrate
5. Nickel (II) Chloride
6. Cobalt Chloride
7. Iron (II) Chloride








After preparing those chemical. lets get started...

Add sodium silicate and distilled water into a beaker in the ratio of 1:2. Stir the mixture well. Leave it settle down for a few minutes.

Now, its time to add those chemicals in one by one~



Products of chemical that added in~ Look like a garden right?

After seeing the product, lets have some photos.









No electricity when the meeting going to end~ But meeting still go on :)
Lets listen to some explanation:





When metal salts are added to a silicate solution, insoluble silicates are formed. A semi permeable membrane forms around the salt. Because the concentration is greater inside the membrane, wter enters the membrane to dilute the concentration solution (osmosis). Osmosis causes the membrane to break. It breaks upward because the pressure of water on the sides of the crystal is greater than that on the top. This process is repeated as a new membrane forms, and an upward growth results.

Metals are mostly from d-block of periodic table (transition metal) since it is coloured.

Reaction taking place is a precipitation of the metal ions with silicate ions. A simplified equation for the reaction taking place with cobalt (II) ions from the metal salt and silicate ions from the sodium silicate solution is as follows: 

Co2+ (aq)   +   SiO3 2- (aq)   --->   CoSiO3 (s)

The cobalt silicate is a semi permeable membrane. Because the ironic strength of the cobalt solution inside the membrane is higher than the sodium silicate solution which forms the bulk of the tank contents, osmotic effects will increase the pressure witin the membrane. This will cause the membrane to tear, forming a hole. The cobalt cations will react with the silicate anions at this tear, forming a new solid. In this way, growths will form in the tanks, these will be coloured and may look like plants. The crystals formed from this experiment will grow upwards, since the pressure at the bottom of the tank is higher than the pressure closer to the top of the tank. Therefore, forcing the crystal to grow upwards.

Last meetings for upper sixes before AGM~ 


Shiuan Yih.
25/7/2013 


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