rates of reactions
DESCRIPTION
Rates of Reactions. Make-up lab Don’t click through the animations too fast! Take your time and make sure the animation is finished before you click again. Collision Theory. Add heat Stirring/shaking Increased Surface Area Increased Concentration Catalyst. - PowerPoint PPT PresentationTRANSCRIPT
Rates of Reactions
Make-up lab
Don’t click through the animations too fast! Take your time and make sure the animation
is finished before you click again.
Collision Theory
So how do we speed up a reaction?
• Add heat
• Stirring/shaking
• Increased Surface Area
• Increased Concentration
• Catalyst
On the left is a list of ways to speed up a reaction; on the right are ways
to slow down a reaction.• Remove heat
• Let it sit
• Decrease Surface Area
• Decrease Concentration
• No Catalyst
HeatIncreasing the heat energy will make the molecules move faster = faster collisions
Shaking/ Stirring
• Adding mechanical energy to the reaction can also increase the speed of the molecules = faster collisions!
Increasing Surface Area
• More surface area = more space for collisions
Change the Concentration
• A ratio of the amount of one substance verses the other substance(s). Increase the concentration of one = more possible collisions.
Higher Concentration Lower Concentration
Catalyst
• Involves using a separate substance added to the reaction to speed it up.
Hydrogen Fuel Cell
Experiment!
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100
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Alka-Seltzer Tablet
Beaker with cold temperature water
Control Test
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Alka-Seltzer Tablet
Beaker with HOT temperature water
Heat Test
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100
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250
Alka-Seltzer Tablet
Beaker with cold temperature water
Stirring/Shaking Test
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100
150
200
250
Alka-Seltzer Tablet
Beaker with cold temperature water
Increased Surface Area Test
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100
150
200
250
Alka-Seltzer Tablet
Beaker with cold temperature water
Changed Concentration Test