10 Practicas De Ciencias En Ingles

Practices of physics, biology and chemistry.

OBSERVING DNA

The main objective of this experiment is to observe DNA without a microscope, using only household materials

. MATERIALS

-Chicken Liver

Liquid-detergent

-Enzymes (pineapple juice)

White-Alcohol

-Blender

-Glass or plastic container

-Beaker or cup with graduations (for babies)

Procedure 1 -. Were cut into small pieces chicken liver. Then placed in a blender and made enough water so that, after 10 seconds of blending, the consistency of cream have.

2.-Then pour the liquid into a beaker through a sieve to remove some parts that have not liquefied enough.

3.-Measured liquid in the container and liquid is added to ¼ of the total liquid detergent. Two . Gently stir with a spoon.

4. - 1 tablespoon enzyme is added and stirred gently and slowly for about 5 minutes. If you mix too fast or too hard can that DNA breaks , which we could not observe it.

5 - Pour the mixture into a tall thin container halfway.

6 - The vessel is tilted and alcohol is poured very carefully, avoiding that WILL mix with the liquid below. After a few minutes you will see a white filaments within the spirit and rising liver mix, detergent and enzymes. We are observing the DNA

COMBUSTION CHEMISTRY OF SUGAR

MATERIALS :

1) A lump of sugar ( bigger is better )

2) Clamps to hold the sugar cube

3) Lighter or heat home

4) A cigar

Procedure: 1) We hold the cube with tongs , and closer to the heat source to try to make it burn .

2) Notice that the thing is not so easy, the lump of sugar will not burn since before it reaches its ignition temperature melts and browns .

3) To make it burn impregnate the sugar cube with cigarette ash and we repeat step 1 , ie hold it with tweezers and bring it to the burner , now you will observe that the sugar begins to be burned and little remains constant flame .

Explanation: The cigarette ash in contact with the sugar acts as a catalyst and causes the temperature needed to start the combustion reaction of the sugar with the oxygen in air is smaller . In this way it is achieved that the sugar starts to burn at a lower temperature at which it begins to melt .

PHYSICS HOME SPIROMETER

Materials:

1) A plastic bottle 3 liter

2) A bucket

3) A piece of transparent hose

Theoretical basis: The operating principle is based on the spirometer air to enter the water displaces water bottle. In addition the property of impenetrability of matter says that two bodies can not occupy the same space at the same time.

Procedure:

1) Graduates bottle with a ruler every 1/4 liter

2) Fill the bucket to the brim with water

3) Fill the bottle with water and place one end of the hose into the bottle.

4) Invert the bottle covering his mouth (bottle) with your hand and place it in the bucket.

5) Take all the air you can and expel it into the hose

6) You will see that the air containing the lungs begin to displace water bottle and bring it into the bucket exceeds

7) When you have no more air, leave the hose, breathing normally and records where the water level reaches the bottle. That's all your lung capacity.

8) Play with others. So go check that according increasing age, greater holding capacity of air in the lungs

9) Make these experiences within a pool or on a patio, where the overflow of water is not a problem.

THE EFFECT OF ATMOSPHERIC PRESSURE

Need:

• A candle

• A glass bottle wide neck

• A bowl with water

Mounting:

Put enough water in the bowl. Place the candle on the water. Turn it with care and support of their elders. When the flame look stable, cover with the bottle upside down.

What's going on?

The candle will stay on for a few seconds, because it has limited availability of oxygen in the air trapped inside the bottle. This gas is necessary for combustion, which produces other gases.

LIQUIDS IN LAYERS

Need:

-A clear plastic bottle

-Water

-Oil

-Glycerin (optional)

-Liquid vegetable dyes

Mounting:

Pour liquid while inside the bottle and observe what takes place. Add drops of food coloring to see them slowly down the liquids and dissolve. Close the bottle with a lid. Now try mixing liquids breaking the bottle. Let stand.

What's going on?

These liquids are mixed together. Always seek separate when they are not being beaten. Some are heavier than others. If you use fat-soluble dye, dye may also fats.

ROCKET LAUNCHER VINEGAR

Materials:

-Cork to plug a bottle

-A bottle

-Tacks

-Tape plastic wrap

-1/2 cup water

-1/2 cup vinegar

-Baking soda

-Piece of absorbent paper 10 X 10 cm

procedure:

Take the piece of paper towel and put a teaspoon of baking soda. I arróllalo well, that fits inside the baking. Weapon cork with ribbons. Prénsalas with tacks. Put the water and vinegar in the bottle.

mounting:

Find a place where the ceiling is high. Put your bottle on the floor and drops with baking paper in the background. Put the cork as hard as you can.

Result:

Soon the liquid will wet the paper towel and then baking soda react with vinegar, producing carbon dioxide. Soon the cork will be launched into space.

What's going on?

When the carbon dioxide gas produced, the pressure inside the bottle increases, releasing the cork

SKIN WATER

Materials:

-Water in a glass beaker

-A dropper

-Soap

-Paper

-Talc or pepper

-A thread

Procedure:

Take a dry glass, fill it with water almost to the top. With the dropper just add as many drops as you can without spilling. See that the water will come above the edge (approx. 0.25 cms.) And this is due to the tension of the water that remains bound molecules. We call this the "skin" of water. Of course, water has no "skin" really, but has a surface tension, as you'll see in this experiment. Now try different objects float on this skin.

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