Homemade glue

This is a non toxic, easy and inexpensive way to do child craft glue.

This needs adult supervision, remember that the kitchen can be a dangerous place to play in.

What we need:

• 1/2 cup hot water,
• 1 tablespoon vinegar,
• 2 tablespoons of milk powder ,
• 1/2 tablespoon of  baking soda,
• water,
• 1 coffee filter, 
• 1 funnel,
• a plastic/ glass containner,
• 1 tablespoon,
• plate.

How to:

1. Mix the hot water and the powder milk until dissolves;
2. Add the vinegar, the milk will form 2 distinct parts, the serum and the curds;
3. Keep mixing this mixture until curds and serum are well separated;
4. Place the filter in the funnel;
5. Place the funnel in the container;
6. Filter the previous mix;
7. If necessary raise a little bit the funnel so the air can flow, remember that air takes up space;
8. When the funnel is full "squeeze" the filter a bit, carefully;
9. Discard the serum;
10. In a small plate, using the spoon, break the serum layer into small pieces;
11. Add one hot water teaspoon and about 1/4 teaspoon baking soda;
12. Mix it all well until the adhesive becomes soft and more fluid;
13. If the mixture is too thick add a little more water, if it has lumps add more baking soda.
14. When not in use the adhesive covering it with transparent paper. 

With time the glue becomes more transparent and liquid. Trash the glue when it starts to smell slightly spoiled milk.

Note:
If the milk does not curdle try:

• add more vinegar;
• heat the mixture;
• use more hot water.

Et voilá!
you can almos eat it

Enjoy!

Dancing raisins in soda

QUESTION:
Will the CO2 released from a water with gas bottle be strong enough to take to the surface 6 raisins?

What we need:

• transparent glass,
• water with gas, the strongest work best,
• 6 raisins

How to:

1. Chose a easy to clean zone near the sink;
2. Fill the glass with the carbonated water, use a medium glass, if its too large the gas will escape to fast;
3. Drop the raisins in the water;
4. Observe.

What happens?
The raisins will go up and down in the water for a while.
Why?
The CO2 gas in water begins to free itself when we first open the bottle. This CO2 travels vertically through the glass until it comes into contact with the air, at this poit the gas is released into the atmosphere.

When the bubbles of carbon dioxide meet the raisins those are immediately trapped in the grape rough skin imperfections, which will do the raisin “move up” to the top. When they arrive at the top CO2 bubbles are released in the air and the raisin falls down o meet another set of CO2 bubbles and go up again, and the cycle repeats itself. This will happen until there is not enough CO2 in the water to elevate the raisins.

Make this demonstration a true experiment:

• Use vinegar and baking soda. This mix will produce CO2. Do the raisins dance? Use plain vinegar with no additives
• Use other carbonated beverages.
• What drink is most effective?
• Try to use drinks with sugar and with no sugar. Do you notice any difference in the dance?
• Repeat the experiment using plain water and effervescent Alka-Seltzer® tablets.

Remember, record all your observations so you can quickly draw conclusions. Use a timer to tell time.

Et voilá!
Raisins dancing!

Enjoy! 

The mysterious blast

Magic Science Tricks video.

TRICK Nº3. The mysterious blast


NOTE: This trick must heave adult supervision.

What we need:

• candles,
• matches,
• sodium bicarbonate, baking soda,
• vinegar, normal, without flavor,
• a glass container, with a large opening.

How to:

1. Light the candles;
2. Leave it burning for a while;
3. Pour the vinegar in container;
4. Add half a measure of bicarbonate;
5. Quickly put your hand over the cup, keep your hand there for a few seconds, until the bubbling calms down
6. Hold the container 1 in above the candle wick;
7. Tilt it as much as you can without the liquid content spill over the candles.

What happens?
The flame extinguish.

Why?
When we mix vinegar and baking soda a reaction happens, in this reaction water (liquid), carbon dioxide (gas) and sodium acetate (liquid) are formed. The bubbling is the result of this.
When we place our hand on the flask we don't prevent the gas to escape, we just slow it down, a small amount of it stay inside the container. When we tilt the container near the candles the CO2 escapes, and as result the O2 (oxygen) concentration drops, resulting in the extinction of the flame. This happens because one of the 3 necessary elements for a combustion is missing- the O2 -Check more information about this.

NOTE: CO2 molecule is heavier then O2 molecule.

That's why CO2 is a extinguishing agent, but like all extinguishing agents it can't be used indiscriminately:

Referências:
http://www.fiocruz.br/biosseguranca/Bis/lab_virtual/fogo.html 
http://www.fire-extinguisher101.com/agents.html

Et voilá!
It's Magic

Enjoy!

Science Magic Tricks for everyone

Today, we bring you a video, from youtube I found this video really cool.

This video bring us 10 magic tricks we can do in a party to stun your friends

Magic tricks list:

1. Light a candle without touch the wick;
2. Balance a soda can on a table;
3. Don't break the plate;
4. Bossy hand;
5. The mysterious blast;
6. Stubborn finger;
7. The ball that returns home;
8. Money mood;
9. Acrobatic matches

NOTE: Never play with fire when you are alone!

Let's check out the real thing, during the week we will see the science behind this:

Et voilá!
It will be amazing!

Enjoy!

Cleanning pennies

A penny is a penny, but we can make them shiny and clean with a little help of chemistry. This is another demonstration using vinegar.

NOTE: Don’t use this method to clean collection coins, this can damage the coin. If you have collector coins or valuable items ask a specialist how to clean them.

What we need:

• pennies,
• vinegar,
• salt,
• a jar, with lid
• tablespoon,
• paper napkin.

How to:

1. Mix 2inches of vinegar with 1 tablespoon of salt in the flask;
2. Close the flask;
3. Stir to dissolve the salt;
4. Open the flask and place 2 or 3 coins inside;
5. Close it again;
6. Wait 1 or 2 minutes;
7. Open and remove the coins, be careful with vinegar smell;
8. Place the coins in the paper napkin to dry;

What happens?
The coins become clean and shiny
Why?
The solution we made with the salt and the vinegar released the residues of the coins, and the coins become clean as new.
This residue is copper oxide, this oxide reacts with the vinegar (acetic acid) and the reaction product remains suspended on vinegar.

Et Voilá!
Clean as new
 
Enjoy!

Bending bones with vinegar, the rubber bone

We can have lots of fun with vinegar. We leave you with another demonstration with this stinky friend.
Bending bones
What? Bending bones? How?

Yes, bending bones, the effect works best if we use a bird bone, that’s because this bones are hallow.

What we need:

• a jar, with lid, big enough to the bone,
• 1 chicken bone, Lucky bone or the leg bone works best,
• Vinegar, no flavors, no additions.

How to:

1. Wash the bone, with running water;
2. Show the bone to your restless, show him/her how hard is to bend it;
3. Place the bone on the jar;
4. Cover it with vinegar;
5. Screw the bottle cap;
6. Let it rest for 3 days, place the jar in a safe place, you don’t want your kitchen smelling like vinegar;
7. Remove the bone;
8. Wash it on running water;

Results:
Bend it, tcham tcham! Is it really a rubber bone? Well it looks like one

Why?
Like our bones, chicken bone have calcium, this mineral gives it hardness.
What does the vinegar do to make this happen?
Vinegar is a weak acid, but it's strong enough to dissolve the bone calcium. Once the calcium gone there is nothing more to make it hard- all that remains is the soft bone tissue. Just like what happened here with the naked egg.
 
Ask your restless to answer this questions:

• Does the number of hours the bone is in the vinegar affects the final outcome? How?
• Does the size of the bone affect the demonstration? How?
• Using different kinds of vinegar will lead to different results?

Et voilá!
A rubber bone

Enjoy!

Explosive lunch bag

Explosions are most of the time messy. Usually it's dangerous, but what Restless Minds bring you today is a nice, cool and harmless prank. 

This demonstration uses the same reaction we saw here, with the volcano, and here, with the balloon.
In this reaction acetic acid reacts with sodium bicarbonate, the product of that reaction is carbon dioxide and water. 

What we need:

• zip lock plastic bag,
• paper napkins,
• 2 tablespoons of baking soda, sodium bicarbonate,
• 1/2 cup of vinegar, without any flavors,
• 1/4 cup of warm water.

How to:

1. First of all, do not do this at home, do it outside in a place you can clean easily.
2. Make sure bag has no holes, fill it with water the easiest way,
3. Empty the bag,
4. Dry it,
5. Place the baking soda on the napkin,
6. Fold it like an envelope,
7. Inside the zip lock bag place the vinegar and the warm water;
8. Quickly but carefully  place the "envelope" inside;
9. Close the zip;
10. Place the bag on the floor and step back, again quickly but carefully;

What happen?
The bag will swell and open with a BANG!

Results:
As we saw here and here, acetic acid (vinegar) reacts with sodium bicarbonate (baking soda) and neutralizes it.
This reaction is very fast and results in the production of CO2- a gas. This gas fill the balloon raising the pressure inside, when the pressure is unsustainable the bag open with a loud BANG!


Chemical reaction:

from here

Et Voilá!

Enjoy!

Fill balloons with carbone dioxide

Today we will see a different way to blow balloons, maybe isn't the most profitable but its for sure the funniest.

We will need:

• Medium plastic bottle (PET),
• big balloon, blow the balloon a couple of times before you use it,
• 1 teaspoon of sodium bicarbonate, baking soda, a bit more if you want a bigger balloon;
• 3 tablespoons of acetic acid, vinegar, a bit more if you want a bigger balloon.
• tape.

How to:

1. Lay down baking soda in the bottle;
2. Place the vinegar in the balloon, use a funnel if you need to;
3. Secure the open end of the balloon to the neck of the bottle;
4. Use the tape to hold the balloon to the bottle;
5. Lift the balloon so the vinegar falls into the bottle.

Results:
Baking soda starts to bubbling when the vinegar touch it, and the balloon fills up.

Why?
A reaction occurs when vinegar (acetic acid) touches baking soda (Sodium Bicarbonate). In this reaction Carbone dioxide is produced, along with water and sodium acetate, as show is reaction:

NaHCO3 (aq) + CH3COOH (aq) ----> CO2 (g) + H2O (l) + CH3COONa (aq)

Carbone dioxide is a gas, thats why the balloon fills up.

Et Voilá!

Enjoy!

Naked egg

Another science experiment with eggs.
With this demonstration we will be able to see the egg yolk, without break the egg shell.

All the eggs have 2 major parts, the yolk and the white. Both this parts are essential to the egg and protected by a thin membrane. This is a double membrane and is easily observed on the flattened part of the egg, here assumes the form of a air bag.

What we are going to do it's simple, we are going to discard from the equation the egg shell, leaving intact the membrane and everything inside.

This essay takes about one week, all depends on the type of acetic acid we use and on the size of the egg.

We will need:

• vinegar, the flat one, with no flavors will work the best,
• glass jar with lid, big enough "to drawn" the egg inside,
• Raw egg.

How to: 

1. Place the egg in the jar;  
2. Cover the egg with the vinegar;
3. Close the jar, tight, to avoid the vinegar to split and the odor to spreading;
4. Store the jar in a cool and safe place, a kitchen cabinet for example;
5. Wait 24 hours;
6. Replace the vinegar with careful, reject the vinegar inside, and replace it with fresh vinegar;
7. Store it again;
8. Wait 6 more days, replace the vinegar each 2 days, tic tac tic tac;
9. Remove the egg from the inside of the jar very carefully, reject the vinegar;
10. Wash the egg with running water, very carefully, the membrane can burst.

Results:
Tell your restless to record everything he/she see/observe.

You can show him/her the jar every 24h so he can see/register the demonstration evolution. This simple gesture stimulates the observation and helps the child to think and ask.

The egg shell is made of calcium carbonate. The chemical reaction between the acetic acid (vinegar) and the egg shell (calcium carbonate), makes the second disappear, in this process bubbling and carbon dioxide are formed. The raw egg remains intact due to the thin transparent exterior membrane.

Try this, and transform the demonstration in a experiment:

• What happens if you place the naked egg against the light? 
• Drop the naked egg from 2in height... not more... in a smooth surface, what happen?
• On the same day you place the raw egg in vinegar, use other options, in different jars:
• use a boiled egg instead;
• use a boiled egg but with no shell;
• After the 7 days what are the major differences between all eggs?

Et Voilá!
A jumpy naked egg

Enjoy!