Our momstown Victoria moms and kids did something incredible at our Little Scientists program last month! Science whiz and on-leave primary school teacher, Glenn Kachmar, demonstrated the amazing properties of both "Magic Mud" and Silly Putty!
Magic Mud is a suspension of cornstarch in water that has the bizarre property of being a liquid when it is resting or moving slowly, but solidifies once you slap, punch or squeeze it. The science behind it? “The cornstarch is ground into such fine particles that the molecules line up like little plates. The plates stay rigid when squeezed or slapped, but slide around when released and there is little or no pressure.” (Dianne Pratt, Hey Kids! You're Cookin' Now!)
Glenn mixed up a huge blue batch and let our lil' scientists dip their hands into it, squeeze it into a solid, and punch the surface which would become instantly hard. Amazing! You can also do a lot of other cool tricks with Magic Mud (also known as Oobleck,) like using sound waves to make it take on life-like movements, or running across a huge container of it!
Magic Mud Recipe:
Stir together approximately:
3 or 4 parts cornstarch
1 part cold water
Optional: several drops of food colouring
Next we made silly putty!
Glenn gave each of us a cup and added Elmers Glue, water and food colouring. We mixed and mixed our ingredients, and then added a solution of borax and hot water. When the ingredients started to solidify, we took them out and started to squish and knead. Voila, silly putty!
Like Magic Mud, silly putty is another non-Newtonian fluid. It has characteristics of a fluid and will form a puddle if left to rest; but it has elastic properties and can stretch and bounce, or even break if given a sharp blow. Our kiddies had so much fun playing with these bizarre properties!
Silly Putty Recipe:
1. Mix 250 ml of hot water with 7 ml of borax powder until all the borax dissolves. Set this solution aside. It is called borax solution.
2. Get a cup and mix 30 ml of Elmers White Glue with 20 ml of water. (Elmers works best!)
3. Add two or three drops of food colour to the glue/water mix.
4. Once the glue, water and colour is mixed together well, ad 20 ml of borax solution. Stir this lal together.
5. Take the mix out of the cup and knead it in your hands (it's messy). Be sure to pop all of the bubbles of glue. More borax solution can be added if it is very gluey. Knead it until it has a consistent texture. You now have silly putty.
-Keep it in a closed ziploc bag when you are not using it.
-Experiment. Does it bounce? Does it stretch? Can you break it?
Kids, do try this at home!
Thank you, Mr. K, for this incredible momstown Little Scientists workshop! We can't wait to see what you have planned for us next!