Bending Straws

Victoria chose to do the bending straw experiment. Below is the scientific explanation of what happens with the straw once put into water...

Bend a Straw with Your Eyes Using the power of your eyes, bend a straw sitting in half a glass of water without even touching it! It sounds like magic but it's really another amazing scientific principle at work. What you'll need: A glass half filled with water A straw 2 eyes (preferably yours) Instructions: Look at the straw from the top and bottom of the glass. Look at the straw from the side of the glass, focus on the point where the straw enters the water, what is strange about what you see? What's happening? Our eyes are using light to see various objects all the time, but when this light travels through different mediums (such as water & air) it changes direction slightly. Light refracts (or bends) when it passes from water to air. The straw looks bent because you are seeing the bottom part through the water and air but the top part through the air only. Air has a refractive index of around 1.0003 while water has a refractive index of about 1.33

Coke and Mentos experiment

Gabriel and Ella chose to do the coke and mentos experiment for the class this week. It was messy but fun to watch what happened. We didn't use diet coke, we tried normal coke and we still got a great result... although I would be tempted for our class to try again with the diet coke.

Diet Coke & Mentos Eruption What you'll need: Large bottle of Diet Coke About half a pack of Mentos Geyser tube (optional but makes things much easier) Instructions: Make sure you are doing this experiment in a place where you won't get in trouble for getting Diet Coke everywhere. Outside on some grass is perfect, please don't try this one in your family lounge!! Stand the Diet Coke upright and unscrew the lid. Put some sort of funnel or tube on top of it so you can drop the Mentos in at the same time (about half the pack is a good amount). Doing this part can be tricky if you don't have a specially designed geyser tube, I recommend buying one from a local store such as Natures Discoveries (NZ) or online. Time for the fun part, drop the Mentos into the Diet Coke and run like mad! If you've done it properly a huge geyser of Diet Coke should come flying out of the bottle, it's a very impressive sight. The record is about 9 metres (29 feet) high! What's happening? Although there are a few different theories around about how this experiment works, the most favoured reason is because of the combination of carbon dioxide in the Diet Coke and the little dimples found on Mentos candy pieces. The thing that makes soda drinks bubbly is the carbon dioxide that is pumped in when they bottle the drink at the factory. It doesn't get released from the liquid until you pour it into a glass and drink it, some also gets released when you open the lid (more if you shake it up beforehand). This means that there is a whole lot of carbon dioxide gas just waiting to escape the liquid in the form of bubbles. Dropping something into the Diet Coke speeds up this process by both breaking the surface tension of the liquid and also allowing bubbles to form on the surface area of the Mentos. Mentos candy pieces are covered in tiny dimples (a bit like a golf ball), which dramatically increases the surface area and allows a huge amount of bubbles to form. The experiment works better with Diet Coke than other sodas due to its slightly different ingredients and the fact that it isn't so sticky. I also found that Diet Coke that had been bottled more recently worked better than older bottles that might have lost some of their fizz sitting on shop shelves for too long, just check the bottle for the date.

The Mentos going in...  Come on Gabe... quickly!  Boom! goes the chemical reaction!  Not so much of a boom with the home brand cola... We were all pretty happy with the results!

Cyber Safety Show

On Thursday we had a couple of people come in to present a show about the dangers of bullying online. They acted out two characters each and these characters portrayed how fast things can go wrong with bullying online if information gets into the wrong hands. We took some photos of the performance for you to see:

Picasso Jigsaw Art

Room 8 learnt about the legend of Maui and the giant fish. It was funny how Maui's brothers said he couldn't go fishing, he was too young to catch anything and when he snuck into their boat and went out fishing with them, he caught the BIGGEST fish possible! The legend tells of how the North and South Island were formed. - The fish-land 'Te ikaroa a Maui' becomes the North Island the hook or 'Te matau a Maui' is Mahia peninsula in the Hawkes Bay. The canoe they brothers were fishing in 'Te waka a Maui' is now the South Island and the anchor holding the boat 'Te punga a Maui' is Stewart Island. After we had learnt about Maui we decided to make a jigsaw art piece of Maui and his canoe. A jigsaw art piece is a Picasso style of artwork. Picasso like abstract art, so it is not meant to be a clean and tidy matched up piece of art. Below I have attached our learning intention, success criteria and the original picture so you can see what we were trying to accomplish. Then I will attach our artwork. We are very proud of our picture.

Hokey Pokey Experiment - Mmmmm...

The science behind Hokey Pokey:
When the golden syrup and sugar are heated it causes a reaction with the baking soda which creates carbon dioxide. The carbon dioxide is trapped in the heavier syrupy mixture which causes it to fluff up into the thick golden mixture. As it cools it sets into a firm solid. 

When broken apart it should have large craters (holes) to show where the carbon dioxide was. 

Hokey Pokey RecipeL

Ingredients

5 Tbsp Chelsea White Sugar
2 Tbsp Chelsea Golden Syrup
1 tsp baking soda

Method: Put sugar and golden syrup into a saucepan. Heat gently, stirring constantly until Chelsea sugar dissolves. Increase the heat and bring to the boil. Boil for two minutes. Stir occasionally, if necessary, to prevent burning. Remove from heat. Add bakingsoda. Stir quickly until mixture froths up rapidly! Pour into a buttered tin immediately. Leave until cold and hard then break into pieces.

 Everyone thought hokey pokey was cool to make because they were going to get to sample it...

 But when we added the baking soda and the chemical reaction happened, there was a chorus of 'WOAH''s from every direction. It was cool to see how one little ingredient can make the sugar and golden syrup go crazy all over the place!

'Eggsperiment' time...

Here we have a simple egg... or so it seems....

Charlotte chose this science experiment to prove that you can't crush an egg when you squeeze it. So we all gave it a shot... The faces that were pulled during this experiment were priceless! Afterwards we found out the reason why you can't crush the egg: - 'If you apply even pressure throughout the egg while squeezing it the egg will withstand the force. However if it is overloaded on one side with pressure it will break. That is eggsellent... get it?! Okay that was pretty silly. It was cool to watch everyone try and break the egg though.