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Friday, 3 August 2012

Week 5 - Water Week! with the Young Professors!

Our theme this week - WATER! Good ol' H2O! AW YEAH!

Some of our Young Professors! Studying the capillary action of water! Although in this picture, Cohen looks more like a Young Superhero!
So last week I was so inspired and had enjoyed Science Week so much that I thought ... lets make Science Week a biweekly event. Soooooo..... Science DosWeek? Two Weeks of Science? Biweek sounds weird, like a tiny little bicycle thats too weak to carry anything ... So I just went with Water Week, when in doubt go with some alliteration! It'll lift your spirits ten-fold!

So Water Week commenced on a spritely and well organized pace! We had the joy of the Young Professors on Wednesday morning, who graced us with their presence and sound mind! The yells of H2O!!!! echoed throughout our library and I was thankful that we have our children's program before we open the library to the public! Although I'm sure Marie, our library director, and Nicole were not amused by our ruckus!

Nevertheless, 'twas a fine morning to bask in the miraculousness of water! Last week, during our Guest Wednesday, Allyson shared the Strange ... But True facts about water! She talked about ice floating in water and how used to it we must be, when in fact its CRAZY! Solids usually sink in their liquid form, right? It makes sense! Solid = dense and compactly sorted molecules that move slightly or vibrarte in place and Liquid = flowing spaced out molecules that fill their container. So you would think a solid would sink, but with ice in water, it floats! And thank goodness for that! Allyson explained to us the characteristics of water that lead to H-bonding and the crystalline-like spacing of water as it freezes into ice and how that also lends to the lovely shapes of snowflakes! 

She also explained how vital floating ice is to our aquatic ecosystems and the world. With floating ice, lakes generally freeze on the surface, leaving fish underneath, still able to swim around! If water sunk when frozen than the tops of lake would freeze in the winter and sink to the bottom of the lake, wrecking havoc on marine life! Also if this occurred in our oceans, icebergs and frozen masses would sink and inevitability mean that the water levels would rise dramatically leaving little to no exposed land on the earth! Whew, TLDR --> floating ice is a strange, but good thing.  

Thank you H-bonds!

So, we started our Wednesday morning talking about water's ability to DEFY GRAVITY!!! - insert Wicked music here - well its not as dramatic as I like make it out to be, but it is quite necessary for plant-life and therefore all life!
With the kids, we talked about watering plants and how their roots absorb the water in the soil, be it from rain or from us watering them! But how is it that water from the soil makes it to the tip-top tops of plants? especially if we think about the tall redwood trees or high reaching trees! The answer? capillary action! 

To demonstrate water's gravity defying abilities I place one cup full of blue water atop a pedestal, or in this case a box of food colouring and then beside it on the table I placed an empty cup. To connect the two empty and water filled cups I took a piece of paper towel and placed it into one cup and into the other (see picture below). Almost immediately as I stuck the paper towel into the cup full of water the water slowly began its ascent up the paper towel! --> capillary action!

The capillary action of water in action! 
Now, one special characteristic of water is its cohesiveness among its molecules, this is due to water molecules inherent polarity that is due to the electrostatic differences across the negatively charged oxygen atom and positively charged hydrogen atoms, because of this charge separation, water molecules have a positive side and a negative side, resulting in a polar molecule. And as we generally learn in our physics classes when we talk about charges, or if we are scrounging around on plentyoffish looking for our one true love, we know that OPPOSITES ATTRACT! So water molecules have a large affinity to fit together with their positive sides to negative sides of another water molecule, resulting in a high cohesion force (the ability of like substances to cling to each other) among water molecules to stay together. 

A fine example of how water beads up due to COHESION! on non-polar material, like leaves. 
You can really observe this cohesion of water molecules, when you place some water on wax paper and how immediately the water beads up into sort of spherical droplets rather than spreading out. These sphere-like droplets form from the attraction among the water molecules and results naturally in sphere shapes, since they have the smallest possible surface area to volume ratio.  

Now in the terms of our paper towel in the water experiment what we see between our two cups, its this cohesion between the water molecules that allow for a string of water to slowly climb the paper towel. Its this action that also occurs in plants that allows for water to travel up a tree trunk or flower stem! 

String of water molecules travelling up
a plant! H-bonds!
So the water in our paper towel moved along the tiny gaps in the fibre of the paper towel, this is due to the adhesive force (the clinging between two dissimilar substances - in this case the paper towel and water) that allows for the water to slowly climb the paper towel, and eventually start to fill the empty cup where the paper towel ends! 

Although I didn't go into huge detail about the hydrogen bonding and cohesion/adhesion forces at work, the Young Professors were enthralled in coming back to watch the water climbing in between our activities for the day! Although I must say, the paper towel we used today worked wonders and the water moved quite quickly!

Here are some of the boys checking out the capillary action of water! Huzzah!

Chesney, Elijah, Cody and Cohen (and some parts of Tyler and an eye of Zoe!)  looking a bit bewildered by water!
After this we had a quick story time with one of my favourite people, Mr. Hank Green, I took an excerpt from this great Crash Course video about water! In the video, Hank tells the story of an eccentric scientist named Henry Cavendish, who was a scientific genius/madman, who pre-discovered many scientific laws and made groundbreaking discoveries about the composition of water, in a time when people thought water was an element in itself! 

Watch the video here in its entirety! The part we watched was from 5:50 - 7:56, although we did indulge ourselves to watch a few more bits and pieces!




After that, I led the kids into our bathroom area to further display some awesome properties of water at work! We had discussed how water is a polar molecule. I talked about some examples of electrostatics that the kids have experienced in day-to-day life! Like shuffling along the carpet and giving your siblings an electric shock or rubbing a balloon against your hair to give yourself the nice mad-scientist coif, and then getting your balloon stuck to the wall on its own! These all happen due to the movement of negatively charged electrons around us! And to demonstrate this affect of a charged object on polar water - and also to show off my avatar-esque water bending abilities (Avatar: The Last Airbender, the show, skip the movie! - trust me the show is awesome!) 

Anyways, what we did was take a simple plastic comb and brush out our hair to displace the electrons to get a charge going on our comb - and our hair! Then by turning on our tap to a nice, small, and steady stream of water, I placed our now charged comb up to the stream and we had some water bending happening! Whew!

This is a fun and easy science activity to try at home! Check out what Science Bob has to say about it on his website: http://www.sciencebob.com/experiments/bendwater.php

After our fun time with bending water, we came back to the children's section of the library to do our fun craft for the day! Some paper tie-dyeing! This is lots of fun! Instead of the traditional tie-dyeing, this craft only requires some paper, shaving cream and food colouring!

Here's the video that gave me the idea! Check it out! Although, us in the library, we were exponentially messier and crazy whilst doing our paper tie-dye!


Here's some pictures of our paper tie-dye!


These are my creations! I tested it out the day before! Success! - I think?



Chesney up to bat!


Elijah's turn!




The kids really enjoyed it! I however used the wrong words when instructing Cody - the first artist - I told him to *smack* his paper down on the table ... oh boy! Those were bad choice of words! I fear there may still be shaving cream hanging on the shelves of the library! shhhhh.... don't tell Marie!!

As for my lab coat... it is now tie-dyed with food colouring, lovely! 

The kids though were hilarious! Cody enjoyed himself and his big boom! And the kids heeded my warning lest we explode the library full of shaving cream, and were a lot more gentle with their craft! Thank goodness! 

The kids had a blast, though. The texture and smells of the shaving cream kept them entertained! After their smooshing escapades they ended up playing with the shaving cream by itself ... which led to more mess in the bathroom! Sorry Marie!!! 

In the end we had a mess of a library and a lovely hanging arrangement of paper!

Tada!






Whew! and we still weren't done! Next, to tie back into our theme for the day I showed the kids some tubs of water! Coloured water! And water water! Fun!



But take a look at these videos and you'll see whats so special that's in these tubs of water!




The kids were blown away by these guys! I absolutely love these! So much fun to play with and look at! I found out about these water beads from Mr. Stephen Fry! Love him! On his show QI they talked about these hyrdobeads and how they are totally "invisible" in water due to having the same refraction of light as water! Great stuff! I showed the first part of this video to the kids to see the trickery of water beads ... although I didn't show the video in its entirety since there is some talk of more mature things... although I'd say its quite immature and humor more appropriate for adults!


So I eventually unleashed the kids to play with the assorted water beads! They had lots of fun and played with it non-stop... well not non-stop, because we eventually HAD to end :( but for quite awhile at least! :) 




Today was again a lovely day for science, wouldn't you agree Dexter? 


Happy reading! Hope you're enjoying  the lovely weather ... I know I've been enjoying the air conditioning here in the library! 



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