14 October 2013

3 Things I've learned :

• We cannot give up easily . 
• If we work hard to achieve something , our hard work will be paid off . 
• Link all the Chapters that have been taught by doing mindmaps . 

2 Things I would like to improve on : 

• Ask the teacher if I have any doubts .
• Doing more mindmaps

1 Thing I would like to try on :

• try to aim A1 for Science 

Experiment Time !

Filtration Process

I did this with my partner , Izzati . Our teacher asked us to try out how to separate salt and sand by ourselves . I read about Filtration ( a process to filter ) through Google and found a video on YouTube about Filtration . 

And there are some photos that my partner and I have taken . 

You can see these photos at izzatisialahh.bogspot.sg

Reflection - Helium Model

3 Things I've learnt

• Helium has 2 electrons , 2 neutrons & 2 protons
• Helium is in the 8 Group
• Helium is a noble gas 

2 Things I would like to improve on

•  The use of materials 
•  The method to finding the number of protons, neutron and electrons

1 Thing I would want to learn 

•  The structure of the different elements to make a compound.

MIndmaps for Acids & Alkali

This is the Mindmap for Acids & Alkali . 

The Periodic Table

Check this out ! Its a Periodic Table Song :)

Videos about Chromatography and Types of Mixtures

A video about Chromatography and Types of Mixtures . You can also find this on YouTube . 

Paper Chromography

Ink Chromography

How to we separate a drop of ink ?

Use the process of paper chromatography to separate the pigments in various markers and then determine the R_f value for each color on your chromatogram.

Materials needed : 

1. Plastic vials
2. Paper clips 
3. Markers in assorted colors 
4. Chromatography paper 
5. Scissors 
6. Pencil

Procedure :

1. Obtain chromatography vials and chromatography strips, and different color markers so that each person in the group will have two chromatograms.
2. Cut one end of the chromatography strip to a point. The bottom of the point will mark the starting point for movement of the solvent (H₂O).
3. About 2.0 centimeters from the bottom of the strip, draw a faint horizontal line with pencil. This will mark the starting point for measuring the migration distance of each color.
4. Using a different color marker for each strip, drop a dot of ink on the center of the horizontal pencil line.  Let this dry a moment & then add more ink to the dot.
5. Add a small amount of water to the bottom of the chromatography chamber. (The ink dot should be ABOVE the surface of the water.)
6. Straighten a paper clip and poke a hole through the top of your chromatography strip
7. Use the paper clip to hang the strip in your chamber. (The straighten paper clip will lay across the top of the chamber.)
8. MAKE SURE THE TIP OF THE STRIP BUT NOT THE INK IS IMMERSED IN THE WATER!
9. Notice the separation of the ink as both the solvent and ink travel up the chromatography strip.
10. Once the solvent front has neared the top of the strip, remove the strip from the chamber and lay it on a piece of paper towel.
11. Immediately mark the solvent front with a faint pencil line.
12. Immediately mark the leading edge of each color with an "x".
13. Measure, in millimeters, the distance the solvent migrated from the tip of the strip to your solvent front pencil line.
14. Measure, in millimeters, the distance each color migrated from the point of origin (pencil line where the ink dot was placed) to the leading edge of the color (marked with an "x".
15. Record all data in Data table 1.
16. Calculate and record the R_f value for each color using the formula below.

R_f = distance traveled by the compound / distance traveled by the solven

Adopted from : http://www.biologyjunction.com/ink_chromatography.htm

Have uploaded this . Do check this :)

Did this with Izzati . 

SIA E-Learning Phase 2 Comic Strip

E-Learning Phase 1 Separation of Mixtures

Magnetic attraction

Separating mixtures containing magnetic materials . Some examples are iron,cobalt and nickel from non--magnetic ones in a mixture .

Procedure involved
Step 1.Place a magnet near the mixture of magnetic and non-magnetic materials.
Step 2.The magnet will attract the magnetic materials from the mixture.

An example of  what it is used for :
Electromagnets are used to remove steel and iron scrap at the junk-yard.

 Filtration

Separating mixture of un-dissolved solids from a liquid. An example of filtration is sand from a mixture of sand and water.

Procedure involved
Step 1.Pour the mixture into a funnel fitted with a piece of filter paper. 
Step 2.Tiny holes in the filter paper allow liquid to flow through it, while the solid particles are too large to do so.
Step 3.Therefore the solid particles will remain on the paper 
Step 4.The solid particles remain on the paper called residue.
Step 5The liquid which pass through called filtrate.

Examples of how it is used for :
Tap water has also been filtered through filter beds to remove solid impurities. Hair in our nostrils trap the dust particles that we breathe in and allow only clean air to pass through.

Evaporation

Separating mixture of dissolved solids from a liquid. Example : common salt from a salt solution.


Procedure involved
Step 1. Pour the solution into an evaporating dish.
Step 2. Heat the solution to dryness to evaporate away the solvent, leaving behind the solute.
Step 3. Make the Bunsen flame smaller when almost all the solvent has been evaporated away to reduce spitting.

How it is used : Industrial applications include recovering salts from solutions and drying a variety of materials such as lumber, paper, cloth and chemicals.

Crystallization

Process to obtain a solid that decomposes on heating from its solution. Examples: sugar crystals from sugar solution.


Procedure involved
Step 1.Pour the solution into an evaporating dish.
Step 2. Heat the solution to evaporate away the solvent until some solid starts to appear or a saturated solution is obtained.
Step 3. Leave the solution to cool.
Step 4.On cooling crystals of the solute that can no longer disssolve in the solution will be deposited as crystals.
Step 5. Filter the mixture to collect the crystals which is the residue.

Uses :Common sugar obtain from sugar solution for daily use. Making hard tack candy.

Paper chromatography

Used to separate the different components in a liquid mixture. Example : To separate the different coloured components that make up black ink.

Procedure involved
Step 1.Apply a small but concentrated spot of the solution on a piece of chromatography paper.
Step 2. Suspend the chromatography paper in a beaker or boiling tube of solvent with the spot above the solvent.
Step 3.Separation takes place because some components of the liquid mixture travel at a faster pace than other components on the paper or any other absorbent material.
Step 4.As the solvent travels up the paper, the mixture is separated into its respective components.

Uses : Analyzing ink dyes for forgery cases.  Detecting trace levels of drugs in urine samples.

Reverse osmosis

Process of forcing a solvent from a region of high solute concentration through a membrane to a region of low solute concentration by applying a pressure in excess of the osmotic pressure.
Procedure involved
Step 1. Water moved across the membrane against the concentration gradient, from lower concentration to higher concentration.
Step 2. Pressure is exerted on the side with the concentrated solution.
Step 3. It force the water molecules across the membrane to the fresh water side.


Uses :Drinking water purification systems used for improving water for drinking and cooking.

Distillation

Separating mixtures based on differences in volatility of components in a boiling liquid mixture. Example : Pure water can be distilled from softdrinks. 


Procedure involved
Step 1. Mixture is heated until the most volatile component begins to boil into a vapor.
Step 2 These vapors are allowed to move down a tube where they are condensed back into liquid at a different location. 
Step 3. In this way, liquids of different boiling points can be separated, or a liquid can be separated from solid impurities.


Use : 
Distillation of herbs for perfumery and medicinals.

Fractional distillation

Process can be used to separate miscible liquids with different boiling points. Liquid with lower boiling point will vaporise first.
Procedure involvedStep 1. Heat mixture containing 2 or more substances.Step 2. Mixure will begin to boil, vaporizing some substances.Step 3. Vapor goes through the fractional distillation column.Step 4. Vapor rises to the top and begins to cool down on its way into the second column. Condensers in commercial processes are the mechanics that cool down the vapor.Step 5. Condensation phase takes place as the vapor is cooled to liquid and finally the substance is transferred into a container on the other end of the second distillation column.


Use :Industries supplying oxygen to hospitals,shipyards.

3D Model

This is the Helium Model . Did this with Izzati . 

What is the difference between Elements, Compounds & Mixtures?

Watch this video to find out the difference between Elements , Compounds & Mixtures . 


http://www.youtube.com/watch?v=nxRGahK7B48

Atoms & Molecules

Watch this video ! It's about Atoms and Molecules . 

http://www.youtube.com/watch?v=vlSOESXQI7o

Differences between metal and non-metal

There are various different elements present on Earth. Everything on earth is made of these elements or of a combination of these elements. The earth is so vast that scientists are still finding and classifying new elements. They are even creating new elements via a combination of the existing ones. Currently, there are 118 recognized chemical elements. These are classified into different categories depending on their physical and chemical characteristics: metals, non-metals and metalloids. Majority of the elements are metallic in nature.

Metals and non-metals differ tremendously in their physical and chemical characteristics. On the periodic table, the metals are separated from nonmetals by a zigzag line which passes through carbon, phosphorus, selenium, iodine and radon. These elements and those to the right of them are nonmetals. The elements just to the left of the line are metalloids or semimetals. Metalloids have properties similar to both metals and non-metals. The elements left of the metalloids are metals.

The distinguishing properties of metals and non-metals are listed below.

Metals

Physical Properties

• Usually solid when in room temperature except mercury, which is liquid
• Have a lustrous or shiny look
• Are good conductors of heat and electricity
• Have a high melting and boiling point
• Have a high density, are heavy for their size
• Are malleable, i.e. can be hammered into sheets
• Are ductile, i.e. can be drawn into wires
• Are opaque as a thin sheet
• Are sonorous, i.e. make a bell-like sound when struck

Chemical Properties

• Have 1-3 electrons in the outer shell of each metal atom
• Corrode easily, i.e. damaged by oxidation such as tarnish or rust
• They lose electrons easily
• They form oxides that are basic in nature
• Have lower electro-negativities
• Are good reducing agents

Non-metals

Nonmetals include carbon, hydrogen, nitrogen, phosphorous, oxygen, sulfur, selenium, halogens and the noble gases.

Physical Properties

• Are not lustrous, have a dull appearance
• Are poor conductors of heat and electricity
• Are non-ductile solids
• Are brittle solids
• May be solids, liquids or gases at room temperature
• Are transparent as a thin sheet
• Are not sonorous, i.e. do not make a bell-like sound when struck

Chemical Properties

• Usually have 4-8 electrons in their outer shell
• They readily gain or share valence electrons
• They form oxides that are acidic in nature
• They have higher electro-negativities
• Are good oxidizing agents

Source : http://www.differencebetween.info/difference-between-metals-and-nonmetals