Sunday, 10 February 2013

Testing the water


EQUIPMENTS:

1. Blue & red litmus paper (Can be obtained from any science supply store)
2. An eyedropper or just a dropper (Can be obtained from any pharmaceutical)
3. A cookie sheet
4. Some rain water (Place a cup on the rooftop during the rain to collect rain water)
5. Some tap water
6. Some pound water
7. Some distilled water (Can be obtained from any science supply store)

INSTRUCTIONS:

1. At first lay out the blue and red litmus paper on the cookie sheet.
2. Now use an eyedropper to place a drop of rainwater on each piece of litmus paper.
3. Write down any kind of color change you see. Wash and then dry your eyedropper after that.
4. Repeat the same process shown in instruction 2 for tap water, pound water and distilled water. Remember to wash and dry the eyedropper after every use.
5. Write down any kind of color change you can see.

RESULT:

Different water sample will change the color of the litmus paper differently.

EXPLANATION:

Normally people assume that water has a neutral pH. But water can contain all sorts of different kinds of dissolved impurities that can change the pH of the water. For example, fresh water from the tap is often slightly basic. That means it can turn the red litmus paper into blue litmus paper. That’s because it can have a lot of dissolved carbon dioxide in it. If the sample from the tap wasn’t fresh, you might not have seen this effect. This is because as tap water sits it becomes more and more flat as the carbon dioxide leaves. The same effect occurs when carbonated soda is left out. Distilled water means water which was turned vapor at first through heat and then turned into liquid water again by cooling the vapor down. Through this process we can have close to pure water. That’s why distilled water has neutral pH and it doesn’t change the color of neither blue nor red litmus paper. Water from the pound can greatly vary its pH because of the impurities produced by nature and/or human. Rainwater normally turns the blue litmus paper into red litmus paper. So the rain water is on the acidic side. There are many pollutants and oxides in the air such as carbon dioxide. These pollutants and oxides get caught in the rainwater as it falls from the sky. Unpolluted rainwater has a pH of approximately 5.6 values. But pH values bellow 5 can be really very harmful for plants and wildlife.

MORE EXPERIMENTS FOR YOU:

1. Use the water from a swimming pool to see what happens.
2. Use the water from a public fountain in this experiment.
3. Use parking lot puddles water and observe.

Thursday, 7 February 2013

Bleaching wool

EQUIPMENTS:
1. A glass jar or a transparent container
2. A scrap of wool fabric
3. Half cup of chlorine bleach (Warning: Direct contact with this chemical can be harmful)

INSTRUCTIONS:
1. At first combine the piece of wool fabric and chlorine bleach in the glass jar or the transparent container. If the liquid isn’t enough to cover the whole piece of fabric then add some fresh water in the glass jar.
2. Now wait 5 minutes.
3. After 5 minutes observe or examine the piece of fabric from the outside of the jar. But do not touch the wool piece.
4. Record or write down your observation.

RESULT:
The bleach turned the piece of wool into a kind of yellow slimy thing instead of turning the wool white!

EXPLANATION:
Chlorine bleach is a very strong base. When bleach reacts with fibers such as cotton, it bleaches very well. Bleach turns almost any color white eventually. Depending on the structure of the chemical it varies the amount of bleach used in this process. Cotton bleaches very well because actually both cotton and bleach are on the same basic side of the pH scale. But wool is an acidic fiber. When wool is combined with bleach a special kind of chemical reaction occurs. This chemical reaction is called neutralization reaction. So eventually the result is that the bleach dissolves wool into something yellow and slimy or more specifically bleach turns wool into a kind of yellow goo!

MORE EXPLANATIONS:
When wool is commercially prepared, it is prepared in a variety of ways to make bleaching possible. For example: wool is soaked in acid before and also after the bleaching process. The extra acid helps neutralize the pH and prevents bleach from dissolving wool.

(DANGER WARNING: You should never combine an acidic liquid with chlorine bleach. Because this could release some potentially dangerous gases in the chemical reaction which would be fatal for you.)

MORE EXPERIMENTS FOR YOU:
  1. Use cotton instead of wool in this experiment to see if it gets bleached or not and how it gets bleached.
  2. Use different kinds of clothes in this experiment instead of wool to see what happens.
  3. Human hair is also acidic. So use human hair instead of wool in this experiment to see how it reacts to the chlorine bleach.
  4. You can also use dog and cat hair in this experiment!

Tuesday, 5 February 2013

Pinecones intelligent weather plan!



EQUIPMENTS:

1. A pinecone (Try a fruit shop!)
2. A bucket full of water

INSTRUCTIONS:

1. At first examine the pinecone very closely and  Note the position of any seeds.
2. Record the observation.
3. Now submerge the pinecone in the bucket of water and leave it for an hour.
4. Record if there is any change in its appearance in every fifteen minutes.
5. After one hour remove the pinecone from the bucket of water and place it in a sunny spot.
6. Examine the pinecone in every thirty minutes until it returns to its former condition.

RESULT:

1. When the pinecone was submerged in water its bracts or scales should close.
2. Once out of the water it takes much longer for the pinecones to reopen its bracts or scales than to close them down.

EXPLANATION:

Pine trees use pinecones to protect their seeds. The scales or bracts of the pinecone close around the seeds when the conditions are too harsh or dangerous for the survival of their seeds. The scales are opened to release the seeds when the circumstances are alright. In a rainy weather the ground becomes damp. So there is a very good chance that the seeds of pinecone will rot before they even have a chance to sprout out. Under these circumstances the scales or bracts of the pinecone closes. This was demonstrated in this experiment by submerging the pinecone into the bucket of water. The reason that the pinecone takes longer to reopen than it took to close in the first place also has to do with protecting the seeds. By doing that it actually protects the seeds from excess moisture. By staying closed until the circumstances dry up considerably the pinecone actually makes sure that the seed rotting chances are as minimized as possible. So as you can see there is a very intelligent and efficient mechanism installed inside the pinecone to protect its seeds as well as to protect its future successors!

MORE EXPERIMENTS FOR YOU:

1. Submerge the pinecone in the oil to see what happens (After submerge don’t try to eat it).
2. Submerge the pinecone in salted water to see what happens.
3. Submerge the pinecone in alcohol to see what happens (After submerge don’t try to eat it).
4. Submerge only half of the pinecone in the water and keep the other half out of the water. See if only half of its body scales or bracts have closed or something else happened.

Glass leaves!



EQUIPMENTS:

1. Some fresh water
2. Leaves from different plants
3. A saucepan
4. Tweezers or tongs (Can be obtained from a stationary shop)
5. A cup of rubbing alcohol

INSTRUCTIONS:

1. Put some water in the saucepan and start to boil it.
2. Now put some leaves in the water and boil it for five to ten minutes.
3. Use a tweezers or tongs to remove the boiled leaves from the water.
4. Then pour the water down the sink.
5. Now fill the saucepan with alcohol in the saucepan and start to boil it.
6. Boil the leaves in the alcohol for ten to fifteen minutes.
7. Now carefully use the tweezers or tongs to remove the boiled leaves from the alcohol.
Transparent Leaf


RESULT:

1. The alcohol should start to turn green while the leaves are being boiled in it.
2. The leaves should be transparent when you remove them from the boiled alcohol.

EXPLANATION:

The plant leaves are green because of a pigment called chlorophyll. Chlorophyll can be found inside the leaves chloroplasts. Chloroplasts are actually an organelle of plant cells. If the chlorophyll is removed from the leaves the green color of the leaves will be gone. To remove the chlorophyll from the plant call the plant cell wall and membrane of the chloroplast is needed to be broken down. Boiling the leaves in the water weakens the plant cell wall and after that boiling those same leaves into the water breaks down the chloroplast membranes. As the leaves are being boiled in the alcohol the liquid starts to become green in color. This color change is caused by the chlorophyll leaking out of the leaves. The rest of the leaf still remains intact. So after removing the boiled leaves from the alcohol it becomes transparent but everything else remains the same.

MORE EXPERIMENTS FOR YOU:

Examine a leaf from this experiment and a regular leaf under the microscope. See if you can find any difference between them.

Monday, 4 February 2013

Get the oxygen out of the leaf!



MATERIALS :

1. A drinking glass or a glass jar or a transparent container
2. Some fresh water
3. A healthy, green leaf which is free from browning
4. A magnifying glass or a convex lance (Can be obtained from any science supply store)

INSTRUCTIONS :

1. At first fill the glass jar i.e. the transparent container with some fresh water.
2. Now submerge the green, healthy leaf you collected completely into the water.
3. Place the glass jar or transparent container under direct sunlight at least for one hour.
4. After one hour examine the submerged with a magnifying glass or convex lance.

RESULT :

There should be many tiny bubbles on the surface of the leaf.

EXPLANATION :

The cells of a plant undergo a process named photosynthesis to survive. The plant uses water, carbon dioxide, chlorophyll, minerals and sunlight to produce energy. Chlorophyll is the substance which normally exists in the tree leafs and gives them green color. When the trees produce energy oxygen is also produced as a by-product. The bubbles which appear on the surface of the leaf under the water are originally oxygen bubbles. This oxygen is created when the cells of the tree undergo photosynthesis. Generally the oxygen should be released into the air. But the leaf is underwater. So much of the oxygen gets trapped inside some bubbles under the water which appears on the surface of the submerged leaf. This is a prof of leaf cell activities.

MORE EXPLANATIONS:

All the plants and also some bacteria use photosynthesis to make sugar. Those who have the photosynthesis system inside them are actually self-depended when it comes to food or energy producing. The bio-chemical reaction which occurs in the photosynthesis 

process actually looks like this:

H20    +            CO2        + Sunlight à C6H12O6 + O2
Water + Carbon dioxide + Sunlight à         Sugar + Oxygen

The sugar must be converted into energy using a process which is called cellular respiration.

MORE EXPERIMENTS FOR YOU :

1. Leave the glass jar or transparent container in total darkness to see what happens.
2. Leave the glass jar in the synthetic or the electric light to see what happens.

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