Crystallisation

The fourth experiment of the year ^-^ (If I'm not wrong) 

In this experiment, we were supposed to make crystals using this method called crystallisation, one of the few separating techniques we learnt. 

Basically, everyone was supposed to:

1. Mix copper (II) sulphate with water until it cannot be dissolved anymore (in the water). 
2. Then, filter out the particles that did not dissolve using filter paper. 
3. Next, we boil the filtrate, which is the liquid left after filtering out the solid particles. 
4. When half of the filtrate has evaporated, pour half of the remaining liquid into a boiling tube, and leave the other half to cool in the evaporating dish
5. Place the boiling tube in a beaker filled with ice water (rapid cooling) 

In the end, both ways of cooling the filtrate (rapid cooling and slow cooling) caused crystals to form. However, if the mixture is not saturated enough, crystals will not form (such as my group). Crystals are formed when water evaporates, which means there has to be a lot of a certain type of particle solute left to have crystals form.

Also, the type of crystals formed by rapid and slow cooling are different. Rapid cooling creates smaller and less defined crystals while slow cooling creates larger and more defined crystals. This is because slow cooling allows the crystals to take a longer time to form, resulting it to become more defined and larger.

 These are the crystals formed through rapid cooling (placed in the ice water).

These are the crystals formed through slow cooling. As you can see, one of the evaporating dishes does not contain any crystals. This is because the solution was not saturated enough (it belongs to my group). D: 

Energy Tower Experiment :D

Hello everyone! (: We had another experiment know as the Energy Tower Experiment, so I'll be writing about it here. 

In this experiment, we were supposed to lift the "Treasure" up to a height of 15cm. The "Treasure"- a 5 gram weight-is to be lifted using reusable energy power, in which case, only water power is available. 

Challenges were faced, surprises were given. We took 1h to create our first experiment, which failed. Then, we spent 5-10 minutes on another experiment then we succeeded. 

Our first experiment involved using corrugated board to make the wheel, but it did not work very well due to water causing the clay to have the inability to stick, and friction about certain parts. The made water wheel was also very unstable. As for the second experiment, we wrote down the procedure detailedly since it was successful, so here it is! 

1. Place two bottles in the sink as stands.

2. Fill them with water to ensure that it does not topple.

3. Shape a block of plasticine to a circular disk

4. Cut off half of the spoon handle and pierce the rest of it into the plasticine at an interval of around 3 cm

5. Insert a wooden skewer through the middle of plasticine disk.

6. Secure the tips of the wooden skewer onto the bottle caps.

7. Tie the string to the weight, then tie the other end onto the wooden skewer.

8. Pour water onto the spokes of the waterwheel.

9. Repeat with the interval between the spokes as 2 cm.

We started off with 6 spokes, but after observation, we realised it was not able to fully lift the load, thus adding another 2 spokes, making it a total of 8. From this, we can see that with more spoons used, the faster the wheel will spin and the load get lifted.

Here are some photos and a video!

At the end of the experiment, my group did a self-reflection, and we realised that to succeed in an experiment, we must not think to complicated and too straight (making a water wheel). Just think of how some things can be used as replacements for others and it still can be successful.