chemical reaction basics
DESCRIPTION
An attempt to make the description of chemical reactions a mini-story. Not the best story by any means, but it was pretty well received by the students.TRANSCRIPT
Chemical ReactionsThe story
Hi there.
This is H2O.So is this.
Meet 2H2O
They weren’t alwaysso happy.
Hmph.You’re out ofcontrol
Bbbllgghh!!
You need me.
I’m important.
Meet O2
He’s light.He’s fast.
He’s crazy!
Meet H2
B-b-b-b-b
One day…Hey!Quit it!
One day…
Chemical Reactions
Bonds are broken and new bonds are formed.
Bonds in H2 & O2 break.
Chemical Reactions
Bonds are broken and new bonds are formed.
New bonds form.
Chemical ReactionsNew substancesare formed.
2 gases react Water is formed
Parts of a ReactionReactants:The chemicals you have before the reaction
H2
That’d be us.
Tbtbbhth! Tbtbbhth!
H2O2
Parts of a ReactionProducts:The substances created in the reaction
H2O H2O
Chemical EquationReactant
sProducts
Parts of a Reaction
Chemical Reactions
During chemical reactions atoms are not created or destroyed. They’re just
rearranged.
2 oxygen atoms4 hydrogen atoms
2 oxygen atoms4 hydrogen atoms
How can you tellif a chemical reactionhas happened?
Let me give you some hints.
Is it a chemical reaction?
If a gas is producedit might be a chemical reaction.Look for the bubbles!
Is it a chemical reaction?
If it changes colorit might be a chemical reaction.Like iron rusting!
Is it a chemical reaction?
If it gets hotterit might be a chemical reaction.
Is it a chemical reaction?
Or…if it gets colderit might be a chemical reaction.
Exothermic ReactionsExothermic reactions release energy.These reactions feel hot.
Endothermic Reactions
Endothermic reactions absorb energy.These reactions feel cold.
Image SourcesWater Molecule
http://commons.wikimedia.org/wiki/File:Water-3D-vdW.png
Oxygen and Hydrogen Moleculeshttp://en.wikipedia.org/wiki/File:Nitrogen-3D-vdW.png
POW!http://www.scribbleonwalls.com/images/products/comc_05.jpg
Shiny Canhttp://www.flickr.com/photos/99347433@N00/315475438/
Rusty Canhttp://www.flickr.com/photos/25149679@N00/466492041/
Burning Matchhttp://www.flickr.com/photos/8070463@N03/3069201840/
Icicleshttp://www.flickr.com/photos/14316700@N08/3075538662/
Bonfirehttp://www.flickr.com/photos/dominicspics/1902322480/
Icy brancheshttp://www.flickr.com/photos/laszlo-photo/426155665/