Reflections on Science experiences,laboratory sessions,field work and excursions 2

​​​​Reflections on Science experiences,laboratory sessions,field work and excursions

Term Two

Week One

This is our first lab lesson for term two. We are all very excited. Mrs Chu taught us how to plot a graph correctly. Mrs Chu reminded us to write the title of the graph (...against...), label the unit and name of the X&Y axis, mark the values on each axis at regular intervals and mark each point with a small cross. We had some practice on them. Next, Mrs Chu taught us how to read the measurements of the thermometer, measuring cylinder, vernier calipers, micrometer screw gauge and spring balance. I had some trouble doing the questions for the thermometer and the measuring cylinder. I had some trouble because there is a curve on the reading. I do not know about it. Mrs Chu told us that that is a meniscus. There is both concave and convex meniscus. Mrs Chu also asked us to do a research on it as Science ACE. I have understood more about the meniscus after the research.

Week Two

This is our second lab lesson for term two. Mrs Chu gave us a revision on Density. I am quite confused about density. We practiced on some of the past years' density questions. They are quite challenging to me. Mrs Chu also reminded us to do the questions in statements ( ... = ... ). Mrs Chu told us that she is very particular about the working. We worked on that for the lab lesson. I hope that I can do well for the density questions.

Week Three

This is our third lab lesson for term two. Mrs Chu gave us a revision on physical quantities and measurements. We were also asked to conduct an experiment at home. The materials needed are 2 eggs, 2 transparent tall glass, tap water and 5 tablespoon salt. Firstly, fill the glasses with tap water until 3/4 full. Next, add 5 tablespoon of salt into one of the glass. After that, stir the glass to ensure that the salt dissolves in the water. Next, add one egg to each glass. Lastly, watch waht happens. I observed that the egg float in the glass of water with salt and sink in the glass of water without salt. From that, I can infer that the salt increases water density and will make the water float. In conclusion. salt increases water density. I feel that the experiment is fun and enriching.

Week Four

This is our fourth lab lesson for term two. Mrs Chu taught us about the inter-conversion of states. That includes melting, boiling, evaporation, freezing and sublimation. Sublimation is a process whareby inter-conversion between solid to gaseous state without passing through the liquid state. Mrs Chu also asked us to do a research on the difference between evaporation & boiling and why melting and freezing takes place at the same temperature. I am also quite confused about it.

Week Five

This is our fifth lab lesson for term two. Mrs Chu taught us about the conversion of units. We practiced some questions. They are quite challenging. We also learn about the periodic table. The left to right of the table has metallic properties to non-metallic properties. The middle part is transition metals that can be mixed with many elements to form a substance. We also learn about the chemical symbols. Metals include aluminium, calcium, copper, mercury, iron and zinc. Non-metals include oxygen, hydrogen, helium, iodine and sulfur. Mrs Chu also taught us about the properties of metallic and non-metallic elements. Metallic elements have High melting and boiling points (exists as solids at room temperature except for mercury which exists as a liquid ) , Good heat and electrical conductors , Ductile and malleable ( can be drawn into wires and bend into shapes without breaking ) , Shiny ( lustrous ) and Sonorous ( Produce a ringing sound when hit ). Non metallic elements have Low melting and boiling point (exists as solids, liquids, or gases at room temperature ) , Poor heat and electrical conductors , Brittle ( Not flexible, easily broken when bend ) , Dull in appearance ( not lustrous ) and Not sonorous. I feel that this lesson is fun and enriching.

Week Six

This is our sixth lab lesson. Mrs Chu taught us more about elements. Elements are made up of only one kind of atom, it is the simplest pure substance, properties similar to those of their atoms and it can't be broken down. We also learn about the uses of different elements. Sulfur is used for medicine, hardening of car tyres and drugs. Carbon is used for pencil lead, charcoal, diamond, soot and fuel. Nitrogen is used for fertilisers and preservatives. Iodine is used for anitseptic and medicine. Oxygen is used for respiration and combustion. Zinc is used for roof and dry cell casings. Mercury is used for thermometers. Magnesium is used for fireworks. Aluminium is used for body parts of aircrafts and cans. Copper is used for wires, water pipes, coins and switches. Chlorine is used for bleaching powder and kills bateria. Fluorine is used for preventing tooth decay. Silicon is used for transistors and manufacture of steel. Calcium is used for the body to grow strong teeth and bones. Iron is used for manufacture of steel, railings, grills and cooking utensils. Lead is used for lead shots and accumulators. Zinc + Copper = Brass and Copper + tin = bronze. Mrs Chu also teach us a lot on Compounds & Mixtures. I find them very interesting.

Week Seven

This is our seventh lab lesson. Mrs Chu taught us about solute and solvent. A solute is a substance which dissolves in a liquid. A solvent is a liquid that dissolves in a substance. After that, we conducted an experiment. We have to burn a magnesium ribbon over a flame and record the observations. We saw a white dazzling light. The ash is white in colour. Mrs Chu also taught us that a new substance is formed if an element or compound changes its physical appearance through chemical reactions like burning. I feel that the experiment is fun and look forward for more experiments.

Week Eight