Reflections+on+Science+experiences,laboratory+sessions,field+work+and+excursions+3

﻿TERM 3
Week One This is the first lab lesson of the term. I am so excited to conduct experiments after a long break. This week, Mrs Chu asked us to conduct an experiment to separate a mixture of salt and sand. Before we begin, we have to determine the difference in properties for the salt and sand. That is simple. Salt is soluble in water but sand is insoluble. Mrs Chu reminded us not to use evaporation but evaporation to dryness term. She taught us briefly about crystallisation. This time, we proceded quickly with the experiment. However i am too impatient, so when i tried to use a stick to move the sand to the side so that the water can filter through it quickier. However, i poked a hole instead. I regretted my actions and apologised to Chuan Bin. Despite this setback, we finished the experiment very quickly and successfully. I feel that lab sessions are very interesting and it is also a better way to understand the concept than doing worksheets.

Week Two This is the second lab lesson. We did an experiment to find out the colours in different brands of black ink using chromatography. I am amazed by the results. The black ink at the start changed into a lot of different colours, purple,yellow,brown,blue,etc. I feel that chromatography is really useful as it can give you the results quickly but accurately. I enjoyed this fun filled experiment a lot.

Week Three This is the third lab lesson. We observed plants and animals cell using a microscope. The cells are very difficult to see. We used our cheek cell for the animal cell and onion cell for the plant cell. I have done this experiment in my primary school before. Nevertheless, it is still very fun and interesting.

Week Four This is the fourth lab lesson. I did the experiment alone as my partner wanted to do with another person. I extracted chlorophyll from leaves and a test for starch. I used a variegated leaf to test for starch at the white portion and green portion. Firstly I place the leaf in the boiling water for 10 minutes to brak the cell structure in the leaf and to stop all chemical reactions taking place and make the leaf more permeable to the iodine solution. Next, i will turn off the heat source to place the leaf in 20ml of methylated spirits in a boiling tube. The leaf will be decolourised. I removed the leaf and add a few drops of iodine to did. The parts that turned blue is the part which contains starch. I concluded that chlorophyll is needed for the plant to make food. It was a fun filled experience conducting the experiment alone. =NOTE) TERM ONE & THREE IS ON ANOTHER PAGE...= =﻿Click the links below to access them...=