Gizmos Student Exploration: Collision Theory

Gizmos Student Exploration: Collision Theory

Collision Theory explores the principles of chemical reactions, focusing on how temperature, surface area, and concentration affect reaction rates. Designed for high school chemistry students, this resource includes hands-on activities and simulations to visualize molecular interactions. Key concepts include the activated complex, catalysts, and the importance of molecular collisions. Ideal for educators and students preparing for exams, this exploration provides a comprehensive understanding of reaction dynamics.

Key Points

  • Explains the Collision Theory and its significance in chemical reactions.
  • Includes hands-on activities to visualize the effects of temperature on reaction rates.
  • Covers the role of catalysts in accelerating chemical reactions.
  • Analyzes how surface area and concentration influence reaction dynamics.
  • newtopiccyclegrowin
142
/ 7
2019
Name: ______________________________________ Date: ________________________
Student Exploration: Collision Theory
Vocabulary: activated complex, catalyst, chemical reaction, concentration, enzyme, half-life,
molecule, product, reactant, surface area
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Suppose you added a spoonful of sugar to hot water and another to ice-cold water. Which
type of water will cause the sugar to dissolve more quickly? _________________________
2. Suppose you held a lighted match to a solid hunk of wood and another match to a pile of
wood shavings. Which form of wood will catch fire more easily? ______________________
Gizmo Warm-up
A chemical reaction causes the chemical compositions
of substances to change. Reactants are substances that
enter into a reaction, and products are substances
produced by the reaction. The Collision Theory Gizmo
allows you to experiment with several factors that affect
the rate at which reactants are transformed into products
in a chemical reaction.
You will need blue, green, and orange markers or colored
pencils for the first part of this activity.
1. Look at the key at the bottom of the SIMULATION pane. In the space below, draw the two
reactants and two products of this chemical reaction.
Reactants: Products:
2. Click Play ( ). What do you see? ____________________________________________
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
2019
Activity A:
Temperature
Get the Gizmo ready:
Click Reset ( ).
Check that the Reactant concentration is set to
1.0 mol/L, the Catalyst concentration is set to
0.00 mol/L, and the Surface area is Minimum.
Question: How does temperature affect the rate of a chemical reaction?
1. Observe: Select the ANIMATION tab. View the animation with No catalyst selected.
What do you see? __________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
When two reactant molecules meet, they form a temporary structure called an activated
complex. The activated complex breaks up into the product molecules.
2. Observe: Return to the CONTROLS pane. Set the Temperature to 0 °C and the Simulation
speed to its maximum setting. Click Play.
A. Describe the motions of the molecules. ____________________________________
___________________________________________________________________
B. Now set the Temperature to 200 °C. How does increasing the temperature affect
the motions of the molecules? ___________________________________________
C. What do you notice about the chemical reaction at the higher temperature? _______
___________________________________________________________________
3. Interpret: Select the GRAPH tab. Click the zoom out button (–) until you can see the whole
graph. What does this graph show? ____________________________________________
_________________________________________________________________________
4. Predict: How do you think temperature will affect the rate of a chemical reaction? ________
_________________________________________________________________________
_________________________________________________________________________
(Activity A continued on next page)
2019
Activity A (continued from previous page)
5. Gather data: Click Reset. A useful way to compare reaction rates is to record the time
required for half of the reactants to react, called the half-life of the reaction. With the
Temperature set to 200 °C, click Play. Click Pause ( ) when the number of reactant
molecules is 10. Record the half-life time in the first space of the table below.
Trial
200 °C
150 °C
100 °C
50 °C
1
2
Repeat the experiment at different temperatures to complete the table. (Note: To get exact
times, you can refer to the TABLE tab.)
6. Calculate: Calculate the mean half-life for each temperature. Fill in these values above.
(Hint: To get an exact mean, first convert each time to seconds by multiplying the minutes
value by 60 and adding this to the seconds. To find the mean in seconds, add up the two
times and divide by two. Convert the answer back to minutes and seconds.)
7. Analyze: What do your results indicate? _________________________________________
_________________________________________________________________________
_________________________________________________________________________
8. Draw conclusions: For two molecules to react, they must collide at just the right angle and
with enough energy to break the original bonds and form new ones. Based on these facts,
why does the reaction tend to go more quickly at higher temperatures?
_________________________________________________________________________
_________________________________________________________________________
9. Apply: Paper must be heated to 234 °C to begin reacting with oxygen. This can be done by
putting the paper over a flame. Why do you think the paper must be heated to start burning?
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
/ 7
End of Document
142
You May Also Like

FAQs of Gizmos Student Exploration: Collision Theory

What is Collision Theory and why is it important?
Collision Theory explains how chemical reactions occur when reactant molecules collide with sufficient energy and proper orientation. It highlights the necessity of these collisions for breaking bonds and forming new products. Understanding this theory is crucial for predicting reaction rates and optimizing conditions in chemical processes. This foundational concept is essential for students studying chemistry, as it connects molecular behavior to observable reaction outcomes.
How does temperature affect the rate of a chemical reaction?
Increasing temperature generally accelerates the rate of a chemical reaction. Higher temperatures provide reactant molecules with more kinetic energy, leading to more frequent and energetic collisions. This increase in molecular motion enhances the likelihood of overcoming the activation energy barrier, resulting in a faster reaction. The document provides simulations that illustrate these effects, allowing students to visualize the relationship between temperature and reaction rates.
What role do catalysts play in chemical reactions?
Catalysts are substances that increase the rate of a chemical reaction without being consumed in the process. They work by lowering the activation energy required for the reaction to occur, allowing more collisions to result in successful reactions. The document explores various catalysts and their mechanisms, demonstrating how they can significantly enhance reaction rates in both laboratory and industrial settings. Understanding catalysts is vital for students interested in chemistry and its applications.
How does surface area influence reaction rates?
Surface area affects the rate of a chemical reaction by determining how much of a reactant is exposed to other reactants. A larger surface area increases the number of collisions between reactant molecules, leading to a higher reaction rate. The document discusses experiments that illustrate this principle, showing how powdered solids react more quickly than larger chunks. This concept is particularly relevant in fields like materials science and chemical engineering.

Related of Gizmos Student Exploration: Collision Theory