Podcast
Questions and Answers
Secondary processes occur in the presence of light.
Secondary processes occur in the presence of light.
False (B)
What is the primary process in photochemical reactions?
What is the primary process in photochemical reactions?
- Activation of molecules
- Formation of products
- Absorption of light (correct)
- Decomposition of reactants
What is the law of photochemical equivalence?
What is the law of photochemical equivalence?
One molecule reacts with one quantum of light.
The primary process involves the absorption of light, leading to the ______________ of molecules.
The primary process involves the absorption of light, leading to the ______________ of molecules.
What is the result of photochemical reactions?
What is the result of photochemical reactions?
Match the following terms with their definitions:
Match the following terms with their definitions:
The quantum yield of a reaction is always greater than one.
The quantum yield of a reaction is always greater than one.
What is the role of light in photochemical reactions?
What is the role of light in photochemical reactions?
What is the primary process in the photochemical reaction described in the passage?
What is the primary process in the photochemical reaction described in the passage?
The chain propagation steps in the photochemical reaction have relatively high activation energies.
The chain propagation steps in the photochemical reaction have relatively high activation energies.
What is the name of the step that produces a large number of HCI molecules before the chain is terminated?
What is the name of the step that produces a large number of HCI molecules before the chain is terminated?
The chain is finally terminated by the combination of chlorine radicals on the walls of the vessel or in gas _____________.
The chain is finally terminated by the combination of chlorine radicals on the walls of the vessel or in gas _____________.
What is the result of the chain propagation steps in the photochemical reaction?
What is the result of the chain propagation steps in the photochemical reaction?
The chain terminating step is exothermic.
The chain terminating step is exothermic.
Match the following steps with their descriptions:
Match the following steps with their descriptions:
What is the primary process in photochemical reactions?
What is the primary process in photochemical reactions?
The law of photochemical equivalence states that one molecule of reactant is activated per quantum of light absorbed.
The law of photochemical equivalence states that one molecule of reactant is activated per quantum of light absorbed.
What is the significance of the ratio 1:1 in photochemical reactions?
What is the significance of the ratio 1:1 in photochemical reactions?
The energy from light is absorbed by molecules at wavelengths around _________ Å.
The energy from light is absorbed by molecules at wavelengths around _________ Å.
Match the following terms with their descriptions:
Match the following terms with their descriptions:
What is the effect of increasing the number of quanta on the rate of photochemical reactions?
What is the effect of increasing the number of quanta on the rate of photochemical reactions?
In photochemical reactions, the energy from light is directly used to break chemical bonds.
In photochemical reactions, the energy from light is directly used to break chemical bonds.
What is the role of Nernst in the development of photochemistry?
What is the role of Nernst in the development of photochemistry?
Study Notes
Photochemical Reaction
- Photochemical reaction is a primary process that forms hydrogen and other molecules through the absorption of light
- This process was discovered by Nernst in 1918
- It involves the absorption of quanta, which are packets of energy, and this leads to the formation of new molecules
Chain Reaction
- A chain reaction is a process that involves the formation of new molecules through a series of reactions
- It involves the absorption of quanta, which leads to the formation of activated molecules
- These activated molecules then react with other molecules to form new molecules, and this process continues until it is terminated
- The chain reaction is characterized by a high yield of products and a low activation energy
Initiating Step
- The initiating step is the first step in a chain reaction
- It involves the absorption of a photon by a molecule, leading to its activation
- The activated molecule then reacts with another molecule to form a new molecule
Propagating Steps
- The propagating steps are the reactions that follow the initiating step
- They involve the reaction of activated molecules with other molecules to form new molecules
- These steps are exothermic and have low activation energies, which means they occur rapidly and repeatedly
Terminating Step
- The terminating step is the final step in a chain reaction
- It involves the combination of two radicals to form a stable molecule
- This step stops the chain reaction from continuing
Characteristics of Chain Reactions
- Chain reactions are characterized by a high yield of products
- They involve the absorption of quanta, which leads to the formation of activated molecules
- They have low activation energies, which means they occur rapidly
- They can produce a large number of molecules before being terminated
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the primary products formed under photochemical reaction in chemistry. Test your knowledge of chemical reactions and processes.
