Disappearing As If by Magic

Why does salt disappear when you put it in a glass of water and stir it? Similarly, where does the sugar go to when you do the same? You can easily wipe off the writings and drawings that you made with a whiteboard marker using a cloth or duster, but when you accidentally use a permanent marker, oops! No matter how hard you scrub, it just would not rub off. Why is this so? 

Solvents are chemicals that will cause something to dissolve, disperse or separate into tinier particles. They will break the chemical bonds of the substance, for example salt, without altering its chemical properties. 

Water is considered a universal solvent because it is able to dissolve most compounds. When salt or sugar is stirred into a glass of water, the molecules that make up the salt or sugar is broken down into smaller units that are not visible with the unaided eye. 

Acetone is a solvent that is used to remove nail polish, whereas ethanol, which is a type of alcohol, is a solvent that is used to remove paint.

So, if you use a permanent marker on a whiteboard by mistake, run to the nearest pharmacy and get some alcohol swabs. These small square pieces of cotton soaked in ethanol will do the trick of wiping off the ink.

Experiment: Making an eggshell go soft

Materials: 
1 egg, drinking glass, vinegar

Steps:

1. Gently place the egg into the glass. 

2. Pour vinegar over the egg to completely cover it.

3. Wait 2 to 3 days. Take the egg out of the glass, and feel the shell.

Fact: 

The vinegar reacts with the calcium in the eggshell, dissolving it. This makes the shell feel soft and rubbery. This shows the importance of calcium to make the shell strong, just like the calcium in our bones.

Glossary:

Dissolve [dih-zolv] to break up or undo a tie or bond

Molecule [mol-uh-kyool] a quantity of a substance, whose weight is numerically equal to its molecular weight 

Compound [kom-pound] composed of two or more parts, elements, or ingredients

Acetone [as-i-tohn] a colourless, volatile, flammable liquid 

Shared by Surain A. Victor

Guest blogger

Can You Hold Fire In Your Hand?

Fire is very dangerous. But, did you know that you actually can juggle it in your hands with a bit of help from science? To do so, you need to make a cloth ball that's made of 100% cotton. You could use your old t-shirts to make it. Take the piece of cloth, then roll it up into a ball. Push the thread through the cloth with a needle. Wrap and sew it into a shape of ball. Make sure it is not synthetic fibre like nylon or polyester because it might burn or melt, with unpleasant consequences. Other materials that you will need to prepare are some hand sanitizer, salt, a lighter, a fire-proof baking or frying pan, tongs and a responsible adult to help you.

To start with, you will need to locate and prepare a safe environment. While these handheld fireballs maintain low temperatures, it can still burn and ignite other materials in the process. Put a pail of water nearby or do it near a sink. In case you panic you can just drop the fireball into the pail or sink. You can also put the frying pan lid over the fireball to suffocate the flame. There is no point in trying to blow the fireball out as it is quite hard to do so. 

First, mix the hand sanitizer with some salt and swirl it in the baking pan. Soak the cloth ball in that mixture with tongs. To further protect your hands, sprinkle some water on your palm to create a barrier from the heat. Use tongs to pick the cloth ball up. Get your responsible adult to light it and then quickly roll the ball back and forth with both hands so that you won’t feel the heat or burn your hands. The trick is to not hold it for too long in one hand. Put it back in the baking pan when you lose your courage handling it.  Ta-da!

Salt is added to the hand sanitizer to give off yellow flames so that you can see it. If salt is not added, the flame will be almost invisible or blue and white in color. It doesn’t hurt when you hold the fireball because ethanol from the hand sanitizer evaporates before the ball gets hot. Another reason is because the heat is not being transferred to the hands as the ball is moving constantly. Here's a video of how we do it in Petrosains:

The process of combustion requires 3 main properties which are oxygen, fuel and heat. In this case, fuel comes from the ethanol in the hand sanitizer and the heat is from the lighter.

The fireballs are reusable. Put them out when they run out of fuel or else the cotton will burn (you can tell this is happening when the ball starts to blacken and produce sooty smoke). If you get to the point where the cotton itself is burning, the fireball will be too hot to hold. Ideally you should extinguish the fireball before it consumes all of its fuel. To reuse it, soak it in more lighter fluid and relight it. 

Lastly, remember to use proper safety precautions and common sense. Don't get burned or set your house on fire. This project is best for adults. If you're not an adult, make sure you have FULL ADULT SUPERVISION and assistance! Stay safe, enjoy and understand the science.

Shared by Melissa
Guest Blogger

Turn Fire Into A Snake!

Have you ever tried making a volcano model using baking soda and vinegar? Or mixing two different food colouring to get a new colour for your icing? If it never occurred that you are already a chemist in your own house, try remembering that each time you make a glass of Milo, or cook a meal, you are actually using principles of chemistry.

Let us explore and try to turn fire into a snake by doing an experiment using baking soda, sugar, methylated spirits and a lighter. You can use matches in case you don't have a lighter. 

What you need are two parts of sugar mixed with one part of baking soda. Mix it on a fireproof surface such as aluminium foil and put a few drops of methylated spirits. You can get it from pharmacies or maybe in your first aid kit. Then, ignite it with a kitchen lighter. To make it grow in shape, it is best if you put some sand as base before adding in the mixture of baking soda and sugar.

So, what do you think will happen? When the baking soda is heated to a specific temperature, carbon dioxide gas is released. Pressure will then build up which causes the black 'snake' to form. The 'snake' is black in colour due to the sugar being caramelized by the heat produced from the combustion. Try it out, it's cool! Now let's watch the video below.

As a safety precaution, have a pail of water nearby or do it near a sink. In case you panic you can throw the mixture into the pail or sink. Don't get burned or set your house on fire! This is a project which requires adult supervision.

With a pinch of adventurous enthusiasm, a tablespoon of science knowledge available online or in books, and a cup of safety precaution, you can turn your kitchen into a fun classroom for yourself and family members!

Shared by Izhana

Learning Specialist, Petrosains

Magic In Your Kitchen!

Let's do magic by using something that you can get from your kitchen! But is it really magic or is it science? Science magic tricks look like "magic," but there is a secret behind the special effects. The secret is a scientific principle or concept from maybe chemistry or physics that makes it look like a 'magic' trick. The great thing is these 'magic' tricks can be used to demonstrate or teach a scientific concept like chemistry in a fun way. Here is a science magic trick using 'red cabbage juice' as a natural pH indicator that changes colors according to the acidity and basicity of the solution! 

But how do you do it? Just peel off six red cabbage leaves and put them in a blender filled half full with water. Then pour the purplish cabbage liquid through a strainer to filter out all of the big chunks of cabbage. Keep the red cabbage juice in a bottle and store it in a refrigerator.

Red cabbage contains a water-soluble pigment called anthocyanin that changes color when it is mixed with an acid or base. The pigment turns red in acidic environments and turns bluish-green in alkaline environments. In chemistry, pH is a measure of the acidity or basicity of a solution.

Now comes the interesting part! Take a small container and fill it with lemon juice. Add red cabbage juice to the container and notice the colour change to red, which indicates that lemon juice is acidic. Watch the video! 

Next, try doing the same with soap solution in a separate container. Add red cabbage juice to it. Notice how the liquid turns to bluish-green, indicating that the soap solution is alkaline. 

Repeat your experiments! Try it with other solutions like detergents and vinegar. You'll find the answer immediately, as to whether it is acidic or alkaline. Usually, an acid is a substance with a sour taste. It also has a pH value of less than 7. However, an alkaline tastes bitter with a pH greater than 7.

Did you know that plants that have colours have pigments in them? Some plants' pigments can react with acid and alkaline and will change colour accordingly. There are many other plants that can be a natural pH indicator too. Next you can try making natural pH indicators using dragon fruit, black berries, grapes and hibiscus too!  



You can also try this at Petrosains and have fun with our current theme, Nature's Kingdom!

Posted by Ayu
Learning Specialist, Petrosains

Of Magic & Chemistry

Towards the end of year 2013, we are celebrating the wonders of science and this time it's having fun with chemistry! The theme is called 'Of Magic & Chemistry'. In conjunction with this theme, we are also giving out a 2-in-1 colourful periodic table and 2014 table calendar to visitors.             

There are many activities listed for visitors to try. Did you know that forensic scientists study how ink breaks down into separate colours in order to solve crimes? We call this chromatography. You can give it a try at Petrosains!

In the ‘Zesty Candle’ activity at Petrosains, you can make your own homemade candle. You need half an orange with the insides scooped out and some olive oil! Orange skin contains a flammable oil with a compound called limonene. Limonene gives oranges and other citrus fruits their distinctive smell! The Zesty Candle made from the orange skin and olive oil produces a fresh citrus scent but with all flammable items, so great care must be taken. 

Our fun science demonstrations on chemistry stimulates you to discover how ordinary works of science can be such an exciting and unforgettable experience! The picture below shows our science communicator performing a science show about ‘Combustion’. Basically he is explaining the three elements that is needed to ignite and sustain a fire, which are fuel, heat and oxygen. 

Hope this will change the mindset that we can only learn and do chemistry in a lab. In actual fact we are free to discover chemical reactions at home using everyday materials. But kids, make sure you have parental guidance if dealing with fire! Or else..







Posted by Ayu
Learning Specialist, Petrosains

Decoding Science Into Arts

Science by itself is intricate. Jargons and complicated theories are always the barrier for the public to understand astonishing discoveries which has won the Nobel Prize. One needs to acquire deep knowledge on Science to digest those findings. However, artist Volker Steger came up with a fresh idea to solve this problem: present science in the form of arts. He challenged the laureates by giving them a blank sheet of paper and a box of crayons to draw their discoveries and this gave birth to the Sketches of Science exhibition. Who else could have imagined such a spontaneous and brilliant approach?

PETRONAS, alongside the Secretariat of the Merdeka Award and the Academy of Sciences Malaysia (ASM) proudly presents The Sketches of Science: Photo Sessions with Nobel Laureates exhibition at the Petronas Gallery (located at the 3rd floor of Suria KLCC). It features 42 portraits of the Nobel Laureates with their sketches which contributed mainly in the main fields of science; Physics, Chemistry and Medicine. 

The moment visitors step into the exhibition, they could see 50 portraits of the laureates posing with their creative sketches. This exhibition allows visitors to explore the art behind the theories from the laureates’ very own perspective. Sketches exhibited brilliantly depict laureates’ minds in presenting their discovery. What is most appealing about the exhibition is it fosters interest to the public that Science is more than just theories; it is also applicable. It is for everyone to view! Not only that, it is interesting that the scientists attempt to simplify their scientific ideas. This concept where science is infused with arts will attract both science enthusiast and the general public. 

Telephone interviews with the laureates themselves are provided; it engages visitors with the laureates. One could feel stronger connection with the sketching as the interview further explains the symbols of each of the portraits that they view. A documentary video and digital presentations in the exhibition makes it even more interactive. In addition, science communicators from Petrosains are assigned each day to assist visitors. They are there to answer inquiries and offer guidance. This creates a new environment where the culture of excellence is injected into the society. 

Sketches of Science is truly unique. Volker Steger also gave an overview of how each laureate reacted to the project and this indirectly showcases the colourful side of their personality. We would like to invite the public to visit the exhibition and gain as much knowledge and inspiration from it. The exhibition is being held until 31st of January 2014, from 10.00 am up to 8.00pm daily except for Mondays. Here's the best thing, admission is free! 

For more information and details on the exhibition click below: 
http://www.galeripetronas.com.my/Pages/Exhibition.aspx?MenuId=2&SubMenuId=6

Shared by Nadrah

Guest Student Blogger