Mad (Kitchen) Scientist

Objective

Review properties of matter--solids, liquids and gasses--and how they can change between those states. Predict the outcome then observe and analyze a chemical reaction. Compare to a baking soda and vinegar volcano and discuss how two substances can combine to form a new substance with properties that are different than the original.

CA Standards--Second Grade

Foss--Solids and Liquids

CA Standards--Third Grade

Foss-Matter and Energy
1.f Evaporation and melting occur when objects heated
1.g 2 or more substances combined, new substance formed with properties different than original materials

Materials

Golden syrup may be hard to find. Call around. It can be purchased online or look in upscale specialty grocery stores or import stores like Cost Plus.
Hokey Pokey: Baking soda, Golden syrup, Sugar
Equipment: Cookie sheet lined with parchment paper, cooking spray, stove, older saucepan or pot, wooden spoon, spatula, measuring spoons
Vinegar
Orange juice
Clear plastic cups

Procedures

Plan is to observe and analyze some chemical reactions by making hokey pokey.
Review the 3 properties of matter--Solids, Liquids, and Gasses. Discuss how things can change state as you take away energy (ie. freezing water slows down the molecules and turns it into a solid or ice) or give it energy (ie. heating water causes it to boil and turn into steam or a gas). Water can also evaporate like when a puddle dries in the sunlight.
Start melting sugar and syrup in a pan on the stove. Ask kids if they can predict the outcome of the hokey pokey.
Meanwhile, ask them if they can predict what will happen when you mix orange juice with baking soda. Pour them all a glass of orange juice but tell them not to drink it. Now, pour a glass of vinegar and add some baking soda to it to make a volcano. Ask them to guess what happened.
- Mixing baking soda (solid) with the vinegar/acetic acid (liquid) produces carbon dioxide (gas bubbles).
Go around the table and add a half teaspoon of baking soda to their orange juice. It will start to bubble.
- Mixing baking soda (solid) with the citric acid/orange juice (liquid) produces carbon dioxide (gas bubbles) to make carbonated orange soda.
Chemical equations are introduced but only explained by describing them as a equation similar to 3+5 = 2 + 6. Two substances combine to form a new substance with properties different than the original. The orange soda is fizzy from the carbon dioxide bubbles trapped in the liquid.
- Mixing baking soda (solid) with the citric acid (liquid) produces carbon dioxide (gas bubbles) and ascorbic acid/Vitamin C (salt)
Ask what else has carbon dioxide bubbles trapped in it that we commonly eat/drink?
- Bread, Beer, Soda, etc.
Proceed with making the Hokey Pokey. Pour onto cookie sheet to cool. Even if it falls, it still tastes good and is holey so you can demonstrate the bubbles.

Hokey Pokey

Ingredients:

1/2 cup sugar

4 tablespoons dark corn syrup or Golden Syrup (tastes better)

1 1/2 teaspoons baking soda

Directions:

Put the sugar and syrup into a saucepan and stir together to mix. You can't stir once the pan's on the heat, though.

Place the pan on the heat and let the mixture first melt and then turn to goo and then a bubbling mass the color of maple syrup - this will take 3 minutes or so.

Off the heat, whisk in the baking soda and watch the syrup turn into a whooshing cloud of aerated pale gold. Turn this immediately onto a piece of baking parchment or greased foil.

Leave until set and then bash at it, so that it splinters into many glinting pieces.