CHEMICAL KINETICS - Reaction Rates

Explain why all chemical reactions need activation energy.

• Energy is needed for the heat of reaction.

• Energy is needed to break the bonds between atoms and ions in the reactants.

• Only endothermic chemical reactions require activation energy.

• Forming the activated complex releases energy.

A high activation energy means the rate of the reaction will be...

• fast because more particles will have the required energy needed for the reaction to occur.

• slow because fewer particles will have enough energy for the reaction to occur.

• fast because fewer particles will have enough energy for the reaction to occur.

• slow because more particles will have the required energy needed for the reaction to occur.

In order for a chemical reaction to be fruitful, two particles must ​ (a)   with sufficient ​​​ (b)   and proper ​​ (c)    

• collide
• energy
• orientation
• temperature
• density
• humidity
• splash
• bounce

Why don't all collisions between particles cause a reaction?

• the particles also need to collide with a catalyst

• not all the particles collide with enough energy

• not all the particles collide at a high enough temperature

• the particles need to collide with each other twice

Which of the following is TRUE for the graph?

• The amount of energy released when making bonds is more than the amount of energy absorbed to break the bonds; therefore, ΔH is negative.

• The amount of energy released when making bonds is less than the amount of energy absorbed to break the bonds; therefore, ΔH is negative.

• The amount of energy released when making bonds is more than the amount of energy absorbed to break the bonds; therefore, ΔH is positive.

• The amount of energy released when making bonds is less than the amount of energy absorbed to break the bonds; therefore, ΔH is positive.

Calculate the change in potential energy between the reactants and the products. (a)  

• -76 kJ/mol
• 139 kJ/mol
• -16 kJ/mol
• 63 kJ/mol
• 47 kJ/mol

B represents

• Potential Energy of Products

• Potential Energy of Reactants

• Change in Enthalpy

• Activation Energy

D represents

• Potential Energy of Products

• Potential Energy of Reactants

• Change in Enthalpy

• Activation Energy

A represents

• Potential Energy of Products

• Potential Energy of Reactants

• Change in Enthalpy

• Activation Energy

Which of the following correctly identifies the reactants of the reaction? 

• carbon dioxide (CO2) and methane (CH4)

• Oxygen gas (O2) only

• Methane (CH4) and oxygen gas (O2)

• Water (H2O) and carbon dioxide (CO2)

• Methane (CH4) only