The accident

Okay welcome back! Today, it would the last post and and as promised, I would tell you what happened in the laboratory. So, relax cause it involves of breaking of beaker.

Okay, the whole class was supposed an experiment of photosynthesis and test for the presence of starch in the leaf. So, we were supposed to boil the leaf in the water and then take the leaf out. But the leaf in inside another beaker so its like there is a small beaker inside a bigger beaker. So, I when take out, it slipped out my hand it go ''Bang''! And, it broke. I went to tell the teacher. He told us to sweep all the glass broken pieces and throw it away. It was very close as the beaker actually almost spill on me. Let me tell you secret, actually I did not wear my goggles.

The lesson here is tell you how important it is to wear a safety goggles before do your experiment. If not, you are risking your eyes. Ok, I would like wish you all luck for your coming end of year exams so wish me luck too!(:

Term 3 science test result

Okay guys, I'm back! You all must be wondering what my result is. As I mentioned in the previous post, I will be working hard towards my goal, which was a B3. Okay, now, its the moment of glory, and my result is......... 27 out of 40. It is a B3 so I have at least achieve my GOAL! But it is still a pity that I am short of 1 mark and I could have gotten an A2. But, what's over is over.

Okay, let me tell you what I did during term 3. Okay, basically, I paid more attention in class than what I paid in class during term 2. I also bought assement books to add on to revision. I also bought guide book to help me. They really did aid me in my revision and I am very glad. The slides in the IVLE also serve their puposes too! Actually, the last four days, I ''chiong''! I spent alot time on revising my science. As my chinese test and science test were on the same day, I actually must admit that I worked very hard for these two tests than my psle. Or maybe the whole term 3. The day before tests, I study still midnight before I sleep.

Okay, guys the learning point for this lesson is that as long you are willing to work hard, they would definitely pays off! So, believe me, work hard and you see the results!(: Look forward for my last post next week, as it is about an accident in the laboraty......

Term 2 science results

Hey guys, I'm back!(: Although I have said the previous post was the last lesson of the session, but this post is compulsory. Maybe another two posts. These three posts all talks about example my term science results, about some laboratory lessons or mt experience with science. Okay, so today about term 2 science results.

Sorry to disappoint you, but my term result, I got 21.5 out of 40 which was a C6. This totally disappointed me. I must admit that I did not study hard for the test mainly because I did not listen in class thus I missed out some points to study. The prefix symbols all these, I actually did not take note that it would be tested. I thought about the marks and I did some reflections. I promised myself to pay more attention in class during term 3 and aim at least a B3( worst case scenario).

So, guys, what I am trying to say is that the results is not the end, but is the reflections you made, take note of the learning points. Make sure you work harder towards your goals and achieve your objectives. So, good luck!(: Me too!(:

The last lesson--Respiration and Photosynthesis

Okay, since today is your lesson, I shall make the lesson quite short. Enjoy! After this session, I would be studying for my final year exam so I would be very busy and still feel free ask me any questions.
What is photosynthesis?

• process by which plants use carbon dioxide, water and light trapped by chlorophyll to make food in the form of glucose, with oxygen given out during the process.
• the word equation is : carbon dioxide + water --(light + chlorophyll)-->> Oxygen + glucose
• takes place in the chloroplast which contains chlorophyll

The importance of Photosynthesis

• make chemical energy available to animals
• removes carbon dioxide and provides oxygen

Photosynthesis makes chemical energy available to animals

• plants provide organisms with food and energy to live directly or indirectly.
• plants are the primary food source because they made their own food.
• plants are called producers

What is aerobic respiration?

• is the process whereby food substances are broken down in the presence of oxygen with the release of energy in the living cells. Carbon dioxide and water are released as waste products.
• word equation is : oxygen + glucose -----> water + carbon dioxide + energy

What is Tissue Respiration?

• process food substances are broken down in living cells
• a large amount of energy is released for the cell to perform different activities

What is External Respiration?

• process of bring the oxygen from the surrounding environment to the cells for tissue respiration to take place.
• also responsible for removing from the body the carbon dioxide and water formed during tissue respiration
  
• breathing is part of external respiration

The importance of Aerobic Respiration:
--Most organisms respire acrobatically. Energy released is used for:

• Growth
• Muscle contractions
• Digestion and absorption of food substances
• cell division
  

Breathing

• The physical process by which respiratory gases are exchanged with the surroundings
• movement that brings the air and into and out of the body

What is Anaerobic Respiration?

• is the breakdown of food substances in the absence of oxygen.
• releases less energy than Aerobic Respiration
• word equation of anaerobic respiration in humans : glucose ----> Lactic Acid + Energy
• word equation of anaerobic respiration in yeast : glucose --> carbon dioxide +Ethanol + Energy
  

Differences between Respiration and Photosynthesis :

Respiration Photosynthesis
-uses oxygen -produces oxygen
-uses food -produces its own food
-does not need chlorophyll -needs chlorophyll
-produce carbon dioxide -uses carbon dioxide
-takes place all the time -requires sunlight
-takes place in all living things -takes place in green plants
-takes place in all living cells -takes place in cells that contains chlorophyll
-energy is liberated -energy is stored in carbohydrate molecule
-oxygen is used, carbon dioxide and water -carbon dioxide and water are used, oxygen is used
are given out
-a destructive process, resulting in the -constructive process, resulting in building up
of carbohydrate molecule
breakdown of carbohydrate molecules
-occurs at all times in all cells, independent -occurs in cells which contains chlorophyll the under the presence of sunlight
of chlorophyll and sunlight

Similarity between Respiration and Photosynthesis

• Both involve energy
• Both involve enzymes

Okay, that's all. Thanks for all your support!! This marks our last lesson!! Goodbye!(:

Compund and mixtures

Welcome back again! Today, we will be talking about compound and mixtures. Button your seats belts and let's rock and roll!

What is a compound?

• is a substance consisting of two or more elements chemically combined together.
  

Examples of compounds:
1. Sodium Chloride Elements: Sodium Chlorine
2. Water Elements: Hydrogen, Oxygen
3. Copper (||) sulfate Elements: Copper, Sulfur, Oxygen
4. Carbon dioxide Elements : Carbon, Oxygen

Characteristics of Compounds:

• has different properties that are different from the properties of its constituent elements
• when compound is formed, there is usually an exchange of energy (in form of heat energy or light energy or both) with their surroundings.
  
• can only be broken down into simpler substances by chemical methods, such as decomposition by heat energy , exposure to light or passing through electric current through it.
• the different elements in a compound always join together in a fixed proportion by mass.

What is a mixture?

• consists of two or more substances not chemically combined together.
  

Examples of mixtures:

1. Blood
   
2. Soil
3. Air
4. Sea water
5. Aerated water

Characteristics of Mixture

• has the properties of its components
• when mixture is produced, little or no energy in the form of heat energy or light energy is given out or taken in.
• can be separated into its components by physical methods like using a magnet, evaporation, filtration and distillation
• can be mixed in any proportion by mass
  

Now, together with the previous lesson. We shall see the differences....

Differences between element, compound and mixture:
Elements Compound
-made up of only one atom -different elements in a compound
- simplest pure substance -combine in a fixed proportion by mass
-have properties similar to -a chemical change takes place when compound is formed
their atom - has properties which are different from its constituents elements
-cannot be broken down - can only be broken down by chemical methods like heating

Mixtures
-components in a mixture are not mixed in any fixed proportion
-no chemical reactions takes place when mixture is formed.
-mixture has properties of substances of which it is made.
-can easily be separated by physical methods like using a magnet

Okay, that's all for today! Hope you have learn something useful today! Enjoy! And remember to tune in for the last lesson of this season!!! Enjoy!(:

Elements

Hey welcome back! Today, we would learning about elements!!(:

What is element?

• a substance which cannot be split into two or more by chemical reaction.
• every element is given a name and chemical symbol
• 1o9 elements are discovered so far
• 92 are natural element while others are man-made
• Most elements are found combined with other elements in the form of ores and minerals

Classification of elements:
http://www.bpc.edu/mathscience/chemistry/images/periodic_table_of_elements.jpg

Elements are classified according to their chemical properties into a chart called a Periodic table which can be seen from the above link.

In the periodic table:

• Each vertical column is called a group
• Each element in a group has a similar chemical properties
• Each group has its own unique properties
• Each horizontal row is called a period
• Elements from right to left show a gradual change from metallic elements to non-metallic elements

Physical properties of Metallic and non-metallic elements

Metallic elements Non-metallic elements
1. High boiling and melting points. 1. Low boiling and melting points
2. Good conductors of heat 2. Poor conductors of heat
3. Good conductors of electricity 3. Poor conductors of electricity
4. Ductile ( can be drawn into wires) 4. Snap easily
5. Malleable (can be beaten into shapes without breaking) 5. Brittle( easily broken)
6. Shiny 6. Dull in appearance
7. High in density 7. Low in density
8. Sonorous 8. Not sonorous

Uses of some non-metallic elements:

1. Carbon Uses: Pencil lead, fuel, constitutes living tissues
2. Nitrogen Uses: fertilizers, freezing agent for food, constitutes plants and animal proteins
3. Sulfur Uses: harden rubber, pesticides, drugs, fireworks
4. Iodine Uses: antiseptic
5. Oxygen Uses: respiration, combustion
6. Chlorine Uses: bleaching powder, kills bacteria, used in making plastics
7. Fluorine Uses: prevents tooth decay
8. Silicon Uses: transistors, manufacture of steel

Uses of some metallic elements:

1. Zinc Uses: to coat iron sheets to make galvanized iron
2. Mercury Uses: thermometers, fluorescent lamps, dental fillings
3. Magnesium Uses: used to distress flares, fireworks
4. Aluminum Uses: aeroplane parts, dink cans, cooking utensils, ladders
5. Copper Uses: electrical wires, water pipes, switches, coins, tanks
6. Calcium Uses: for the body to grow strong teeth and bones
7. Iron Uses: manufacture of steel, railings, grills, cooking utensils
8. Lead Uses: lead shots, accumulators
   

Okay, that;s all for today's lesson. Hope you and enjoy and remember to tune next week for the lesson on compounds and mixture! (:

Solution and Suspension

Hi people! Welcome back!:D I hope you had a better understandings of classification of matter through the previous lesson. Okay, today's lesson. we would be learning about what is a solution and suspension. Now, tighten your seat belts and lets rock and roll!

Firstly, before you learn what is a solution and suspension, you know these things first: What is a solute?
What is the solvent?

Basically, a solute is:

• a substance that dissolves.

And, a solvent is:

• a substance that a solute dissolves in.( forms the main part of the solution.)
  

Thus, a solution is:

• a mixture formed when 1 or more solute dissolves in a solvent.
• can be of any physical state.
• water as solvent is called aqueous solution
• when a solution is formed, the solute breaks down into tiny particles such as atoms and molecules that mix completely and evenly with the particles of the solvent.
  

And, a suspension is:

• when a solid solute does not dissolve in the solvent and are sufficiently large to settle to the bottom over time

Solution and suspension's appearance:
Solution Suspension
-Homogeneous mixture -heterogeneous mixture
-clear solution, uniform throughout -cloudy and uneven

What is a saturated solution?
-one which contains the maximum amount solute dissolved in a certain amount of solvent at a particular temperature.

What is solubility?
-the maximum mass of a solute which can dissolve in 100g of a solvent a particular temperature.

Factors that affect solubility

1. Nature of solute
2. Nature of solvent
   
3. Temperature of solvent

What is rate of dissolving?
-time taken for the dissolve process, from the time the solute is added to the solvent, until it has completely dissolved

Factors that affect the rate of dissolving

1. Surface area of the solute ( the smaller the particle size, larger the surface)
2. Temperature of the solution (higher the temperature)
3. Rate of stirring (faster the rate of stirring)

That's all for today's lesson. Thank you for support. I hope this lesson will once again benefit in your studies. Remember to tune again next week for a new lesson! Enjoy! :D Feel free to ask me and doubts.

Classification of matters

Hello! Welcome to my science e-port folio again! Did you get a better understanding of the previous lessons? I am sure you do. Well, today, we would be learning about classification of matter and kinetic Particle Theory. And,you get to learn to explain inter-conversion of states in terms of kinetic particle theory. All right, tighten your seats belts and lets rock and roll!:D

Remember matter? It occupies space and has space and also can be living and non-living things. It can exist in 3 states :

• solid( fixed volume, fixed shape and cannot be compressed)
• liquid( fixed volume, no fixed shape and cannot be compressed)
• air( no fixed volume, no fixed shape and can be compressed)

What is kinetic Particle Theory?
All matter ae made up of tiny particles. These particles are in constant, random motion.

Firstly, melting is a change from solid to liquid state. But, what happens to the particles of the solid that is heated until it melts?

1. heat energy absorbed is converted to kinetic energy
2. Particles vibrate faster about fixed positions.
3. Vibrates become sufficient to weaken attractive forces between particles.
   
4. Particles no longer in fixed positions.
5. Particles now slide over one another.
6. Substance is now in liquid state.

Freezing

1. Energy is given out by particles in the liquid.
2. Particles begin to lose kinetic energy and move more slowly.
3. Particles no longer have enough energy to move freely.
4. Some particles start to settle into fixed positions
5. All pacticles settle and vibrate at fixed positions.
6. Substance is now a solid.

Boiling

1. Heat energy absorbed is converted to kinetic energy.
2. Particles gain kinetic energy and start to move faster as the temperature rises.
3. Particles throughout liquid have enough energy to overcome the forces holding them together.
4. Particles can now spread far apart and move rapidly in more directions.
5. Substance is now in gaseous state.

Condensation

1. Heat energy is given out.
2. Particles begin to lose kinetic energy and move more slowly.
3. Particles no longer have enough energy to move far apart.
4. Particles move slow enough for the gas to change to a liquid.

Ok, now we have come to an end to our lesson. Look forward for the next lesson. Stay tuned! Enjoy!:D

Density and Units conversion

Hey welcome back again! Today lesson would be slightly shorter. We would be learning about density and units conversion. So, enjoy!:D

What is density?
-Density describes the degree of compactness of a substance.
-Density is mass per unit volume
-The formula is: p=m/v

Example: Water sinks when water and oil are placed in a bottle. Why? It is because water is denser than oil but it is NOT heavier than oil.

Units conversions
On the previous lesson, you have learn that the importance of units and its conversion. Now, let us learn how to convert a unit to another unit example from one meter to centimeter.

Examples:

Since 1 kg = 1000 g and 100 cm = 1 m

1kg/1000g=1 100cm/1m=1

To express 15 mm in m:
Since 1 m = 1000 mm

1m/1000mm=1

Therefore: 15mm/1 x 1m/1000mm = 0.015m

Measurements and Units

Hi! I'm back! Today, we would be learning a new lesson--Measurements and Units. In today's lesson, you would learning the importance of units, and what are some of the measurements instruments and precautions to take.

Measurements Instruments includes:
-ruler ( accurate to 0.1cm)
-measurements tapes
-engineer's caliper
-vernier caliper (accurate to 0.01cm)
-micrometer screw gauge (accurate to 0.01cm)
-and many more....

Precautions to take when using a ruler.:
-avoid parallax errors by putting your eyes at the same level as the markings of the scale
-eye should be put perpendicularly at the mark of the scale

Precautions to take when using a vernier caliper:
-Make sure the instrument is clean and make sure it works ( no forced friction between vernier scale and main scale)
-Check for Zero error( error resulting in the wrong collaboration of the instrument)

Precautions to take when using micrometer screw gauge:
-Never tighten the screw too much
-Check for zero errors
-Make sure it is clean at the ends of anvil and spindle before the experiment

Now, units is very important. Using the wrong units may result in fatal accident like the flight 143. The ground did not put enough fuel on the plane. Fortunately, no one died. What had caused the problem? The metric changeover in Canada should have been by further education on the airline's part. The ''conversion factor'' of 1.77 was actually the fuel's density in pounds per liter, not kilograms. The fuel's density kilograms per liter is 0.803.

Introduction to Science

What is science?
-it is a systematic knowledge that is capable of resulting in a correct prediction or reliable outcome.

If you want to be a scientist, basically you need yo these attitudes:
-Curiosity
-Positive mindset
-Perseverance
-Cooperation with others
-and many more...

For this blog post, we would learning about scientific inquiry and the safety rules in a science laboratory.

First, scientific inquiry.Basically, it includes:
-Being curious and courageous
-Reflect on findings
-Asking questions
-Making observation
-Thinking out of the box
-Refining understandings
-and many more...

Secondly, safety rules in science laboratory.
Why do we need to observe rules in a science laboratory? What are some of the rules we must observe? The following are the general rules we must follow in a science laboratory:
-Always open all doors and windows unless otherwise instructed by the teacher
-Never enter a science laboratory without a teacher's permission
-Never carry out experiments without the teacher's permission
-Never taste the chemical unless you are instructed to by a teacher
-Never pour unused chemical back to its container
-Never eat or drink in the science laboratory
-Always wash your hands after ALL laboratory work.

Next, the followings are the rules we must follow when we heating or mixing chemicals:
-Always wear a safety goggles
-All flammable substances should be kept away from a naked flame.
-Never point the mouth of a boiling tube to you and your friends

Okay, ever wonder what to do when accidents happen in a science laboratory. What should you do in that situation? The following are basically what you do:
-Report all injuries, accidents, spillage to your teacher immediately
-If chemical come contact with your mouth, spit it into the basin and rinse your mouth with plenty of water.
-If chemical come in contact with any parts of your body or shirt, wash thoroughly with water and report to your teacher.

Okay, its done. I hope you have learnt something. Enjoy and look forward for my next post!:D

Introduction

Welcome to my science e-portfolio blog!! Where you can basically get a summary of what i have learnt in school. Well, this platform can also facilitate you in your science if you do have trouble in science. I do not really excel in science but i will do my best to help if i can. Okay, i am William Zhao from class 1o3 of Hwa Chong Instituition. So far, my science tests results are like rollar coaster but i am still trying my best to improve and i really do see improvement. Okay, enough talk, i hope this blog can really help you even if its a little. Enjoy!:D