Science in the kitchen: Eggs and Vinegar

So, J asked if he could perform an experiment at home that he read about in one of his Horrible Science books. I had a look at it and realised that we had all the ingredients in our kitchen and nothing seemed explosive or particularly messy…so why not?

Warning: Science! Also puns. Lots of EGG-ceptional puns. You’re going to crack up. Seriously. Omelettin’ this happen, yo. 

J’s Question: What happens when you soak eggs in vinegar?

What we used to answer J’s Question:

  1. One hard boiled egg
  2. One raw egg
  3. Vinegar (we used apple cider vinegar, but white vinegar probably works best)
  4. Glass jars of roughly the same shape and size.

What we did to answer J’s Question:

1. Label the jars and place the respective eggs inside.

egg-vinegar-experiment

2. Cover each egg with an equal amount of vinegar and watch the science happen.

  • J’s Observation #1: Bubbles appeared on the surface of the eggs
  • EGG-CITING SCIENCE! The acetic acid in the vinegar reacted with the calcium carbonate of the eggshell, releasing carbon dioxide gas as bubbles!

experiment-science-egg-vinegar

3. Leave the eggs in the vinegar for three days. Check on the eggs and see if there is more science happening

  • J’s Observation #2:There is a yucky white scum floating on the surface of the vinegar
  • EGG-CELLENT SCIENCE! Calcium acetate is a the other byproduct of the chemical reaction between the vinegar and the eggshell, and is a white solid at room temperature.

4. Remove the eggs from the jars and rinse away the vinegar (and any residual eggshell) under running water. Remember to EGGS-ercise caution whilst doing this.egg-vinegar-experiment-science-membrane-diffusion

5. Place the eggs on a plate and allow them to dry. Compare the two eggs.

  • J’s Observation #3: Both eggs have a smooth and waxy surface. The raw egg is much bigger than the boiled egg (Debs G: It is EGG-ceptionally large) after it has been soaked in vinegar
  • EGG-STREME SCIENCE! The eggshell completely dissolved in the vinegar. Underneath the eggshell is the egg membrane. Some of the water from the vinegar has moved across the membranes to the inside of the raw egg, but the contents of the egg did not leak out. This is because the egg membrane is semi-permeable and allowed only certain sized molecules through. The egg membrane is stretchy, so the egg swelled as the water moved inside it. Water moved inside the egg because the contents of the egg contained less water than the vinegar outside the egg. The process where a solvent (such as water) moves from a lower concentration solution (such as vinegar) to a higher concentration solution (such as egg white) is called osmosis.

science-egg-vinegar-boiled-raw

 

6. Drop both eggs from increasing heights and see what happens.

  • J’s Observation #4: I can see the yolk wobbling about inside the raw egg but not in the boiled egg. When I dropped them, both eggs bounced but when I dropped them from very high up, the raw egg burst like a water balloon (Debs G: It was EGGsplosive). The raw egg is liquid, but the boiled egg is solid.
  • EGG-TRAORDINARY SCIENCE! Eggs are full of protein. Proteins are made up of amino acids. When the egg is boiled, the heat messes up the amino acid bonds that hold the proteins together and give them a particular shape and form. The egg protein changes in form and appearance, becoming hard and solid. When proteins change from their original form into a new form, this is called denaturation.

So, don’t be a chicken. Get cracking and hatch a plan to make Science happen in your own kitchen!

These are the yolks, kid. These are the yolks.

 

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Weekend Special: Science Street Fair 2013 at the Science Centre Singapore

Hurrah, hurrah for Science Centre Singapore’s 35th Anniversary!

This year, the Science Centre Singapore is throwing a huge celebration with an Open House from the 8 to 11 November 2013, held in conjunction with Singapore’s first Science Street Fair. This is a carnival with over 100 stalls featuring science-related performances, games and hands-on workshops for all the family. Admission to the Science Centre is free during the open house, although some of the stalls and workshops require the purchase of coupons.

This is a brilliant time to visit, as there are a ton of brilliant science demonstrations going on at all hours and purchase of Science Street Fair coupons include discounts to other gated attractions such as the new Titans of the Past Exhibition (which is definitely worth a visit).

We started off our visit with the Fire Tornado Show, which takes place at 3pm and 7pm daily during the Open House. J and Little E were both awed by this impressive display which is contained within a 6 metre high glass and steel structure with angled vents at the bottom that draw in air to feed the flames and twist them into a tower of fire.

open-house-science-street-fair-singapore

Feeling hot, hot, hot!

The Fire Tornado exhibit is an original masterpiece designed by local inventor, Dr Her-Mann Tsai, who is a fellow of the Science Centre Singapore. Yay, Singapore!

After the flames died away, we headed over to the Inflatable Planetarium. J and Little E are big fans of the BBC series ‘Wonders of the Solar System’ so I knew that they were sure to enjoy this chance to view all the constellations and planets which are difficult to see in our city-lit night sky. The Planetarium shows are at 11:30am, 1.30pm, 3.30pm and 5.30pm, and cost $5 a person (they were kind enough not to charge me for my two preschoolers).

There is a limit of 40 people per session, so we signed up early and stuck around to do some crafts. The kids busied themselves making a paper sundial and a pin-hole model of the constellation ‘Sagittarius’.

constellation-pinhole-sundial

Sun-and-Starcraft

Afterwards, we were herded into the inflatable planetarium where J listened intently to the science educator as he showed us the different constellations and talked about the planets.  Little E just lay on her back, looking up at the little dots of light and pointing excitedly.

The projected images were amazingly clear and detailed, and we could even zoom in on the surfaces of distant planets and identify surface landmarks. It was like taking a trip through space!

street-science-fair-2013-education

Indoor stargazing is fun!

We then headed round the corner towards the Watson DNA Lab, where there are DNA Extraction Workshops at 11am and 3pm (with an extra session at 4pm due to high demand!) at $5 a participant. I was able to sneak a peek into the lab, where kids were extracting DNA from samples of fruits and grains.

DNA-science-kids-experiment

Mini-Forensic Scientists at Work!

(If you take a closer look, you can see Meips and Noey with V from Life is in the Small Things! She writes about the DNA extraction workshop here.)

We decided to give the DNA workshop a miss as I felt the learning content would be too complicated for preschoolers. Instead, I let the kids craft their own double-helix strand to take home.

ecorider-gyrospin-beatbox

Fun rides, performances and displays

It was really fun exploring the various corners of the Science Centre! There was so much going on there, we didn’t get a chance to see all of it before it was time to head over to the Atrium for the Tesla Coil Chainmail Demonstration.

science-street-fair-2013

3.5million volts of electricity goes ZAP

This demonstration takes place 12pm, 5pm and 8pm during the Open House, and it is spectacular to see the purple fingers of electricity arcing through the air! J and Little E had to cover their ears because it created an incredibly loud buzzing noise.

As if that wasn’t impressive enough, a knight appeared clad from head to toe in heavy chainmail and clanked his way to a podium. All of us watched with bated breath as he was zapped with 3.5million volts of electricity[1].

It was amazing, watching this guy basically get hit by lightning and survive. You could even see the electricity passing through the chainmail and reappearing as tiny streaks of light from his fingertips.

electricity-experience-science-family

Chainmail dude makes KABOOM!

Finally, the knight drew his rapier and directed the electricity towards two balloons filled with highly-combustible hydrogen gas. The balloons each exploded with a satisfying ball of fire to the combined ‘WHOOOOA’ of the crowd. AWESOME. STUFF.[2]

After this, we headed over to Snow City (admission is 50% off with Science Street Fair coupons) to freeze our noses tobogganing down an icy slope in a rubber tube[3]. There are also some super cool science experiments to take part in at Snow City, including making instant ice cream!

It was close to dinner so we decided to head off, although there was still so much to see and do at the Science Street Fair. We might have to go back again for another round!

Science Centre Singapore: 15 Science Centre Road, Singapore 609081


1.Well, all of us except my dear boy, J, who screamed “FRY HIM!!!!!”
2.It made you want to punch your fist in the air and yell “SCIENCE!!!!!”
3.I would only recommend this activity if you have never had the opportunity to see or play in snow before. It can be tedious after a while, especially if you are not adequately dressed for winter weather.