KKHA Arts,SMGL Commerce,SPHJ Science College,Chandwad

1. Medicine bottles are often made with darkened glass _______

To prevent the drug from photodegradation

To allow the photodegradation of drug

To reduce the cost

To allow oxidation of drug

Medicine bottles are often made with darkened glass to prevent the drug from photodegradation. This is because certain medications can be sensitive to light and can degrade when exposed to it. By using darkened glass, the amount of light that reaches the drug is reduced, helping to maintain its stability and effectiveness.

Explanation

Medicine bottles are often made with darkened glass to prevent the drug from photodegradation. This is because certain medications can be sensitive to light and can degrade when exposed to it. By using darkened glass, the amount of light that reaches the drug is reduced, helping to maintain its stability and effectiveness.

2. In photochemical reactions, absorption of _____ radiations takes place.

ultraviolet and visible

Radio

Only visible

Visible and x-rays

In photochemical reactions, absorption of ultraviolet and visible radiations takes place. This is because photochemical reactions involve the absorption of photons, which are particles of light. Ultraviolet and visible radiations have the appropriate energy levels to excite the electrons in molecules and initiate photochemical reactions. Radio and x-rays do not have the appropriate energy levels to cause these reactions.

Explanation

In photochemical reactions, absorption of ultraviolet and visible radiations takes place. This is because photochemical reactions involve the absorption of photons, which are particles of light. Ultraviolet and visible radiations have the appropriate energy levels to excite the electrons in molecules and initiate photochemical reactions. Radio and x-rays do not have the appropriate energy levels to cause these reactions.

3. In _____ reactions, molecules absorbing light do not themselves react but induce other molecules to react.

Photosensitized

Thermal

Irreversible

Dark

Photosensitized reactions involve molecules that absorb light and transfer the energy to other molecules, causing them to react. In these reactions, the molecules that absorb light do not undergo a chemical change themselves, but instead, they facilitate the reaction of other molecules. This process is commonly seen in various biological and chemical systems, where light-absorbing molecules, known as photosensitizers, are used to initiate reactions in other molecules.

Explanation

Photosensitized reactions involve molecules that absorb light and transfer the energy to other molecules, causing them to react. In these reactions, the molecules that absorb light do not undergo a chemical change themselves, but instead, they facilitate the reaction of other molecules. This process is commonly seen in various biological and chemical systems, where light-absorbing molecules, known as photosensitizers, are used to initiate reactions in other molecules.

4. . Which of the following are the principle laws of photochemistry?

Grothus-Draper and Stark-Einstein law

Raoult’s and Dalton’s law

Raoult’s and Henry’s law

Lambert’s and Beer’s law

The principle laws of photochemistry are Grothus-Draper and Stark-Einstein law. The Grothus-Draper law states that only light that is absorbed by a molecule can bring about a photochemical reaction. The Stark-Einstein law states that for each photon absorbed, only one molecule is activated to undergo a photochemical reaction. These laws are fundamental in understanding the interaction between light and matter in photochemical processes.

Explanation

The principle laws of photochemistry are Grothus-Draper and Stark-Einstein law. The Grothus-Draper law states that only light that is absorbed by a molecule can bring about a photochemical reaction. The Stark-Einstein law states that for each photon absorbed, only one molecule is activated to undergo a photochemical reaction. These laws are fundamental in understanding the interaction between light and matter in photochemical processes.

5. Vision is initiated by a photochemical reaction of ______

Rhodopsin

Hydrogen Chloride

Mercapton

Enzymes

Vision is initiated by a photochemical reaction of rhodopsin. Rhodopsin is a light-sensitive pigment found in the rods of the retina in the eye. When light enters the eye and reaches the rods, it causes a chemical change in the rhodopsin molecules, triggering a series of reactions that ultimately result in the generation of electrical signals that are transmitted to the brain, allowing us to see.

Explanation

Vision is initiated by a photochemical reaction of rhodopsin. Rhodopsin is a light-sensitive pigment found in the rods of the retina in the eye. When light enters the eye and reaches the rods, it causes a chemical change in the rhodopsin molecules, triggering a series of reactions that ultimately result in the generation of electrical signals that are transmitted to the brain, allowing us to see.

6. Which of the following is an example of photochemical reaction?

Photosynthesis

Decomposition of ammonia

Formation of NaOH

Decomposition of HCl

Photosynthesis is an example of a photochemical reaction because it involves the conversion of light energy into chemical energy. In this process, plants use sunlight, water, and carbon dioxide to produce glucose and oxygen. The sunlight provides the energy needed to drive the chemical reactions that occur in the chloroplasts of plant cells. This reaction is essential for the survival of plants and is responsible for the production of oxygen in the atmosphere.

Explanation

Photosynthesis is an example of a photochemical reaction because it involves the conversion of light energy into chemical energy. In this process, plants use sunlight, water, and carbon dioxide to produce glucose and oxygen. The sunlight provides the energy needed to drive the chemical reactions that occur in the chloroplasts of plant cells. This reaction is essential for the survival of plants and is responsible for the production of oxygen in the atmosphere.

7. Which of the following is not an example of a concerted reaction?

Diels-Alder

. E2

SN1

SN2

The Diels-Alder reaction, E2 reaction, and SN2 reaction are all examples of concerted reactions, where the bond-breaking and bond-forming steps occur simultaneously. However, the SN1 reaction is not a concerted reaction. In an SN1 reaction, the bond-breaking step occurs first, leading to the formation of a carbocation intermediate, followed by the bond-forming step with the nucleophile. Therefore, SN1 is the correct answer as it does not fall under the category of concerted reactions.

Explanation

The Diels-Alder reaction, E2 reaction, and SN2 reaction are all examples of concerted reactions, where the bond-breaking and bond-forming steps occur simultaneously. However, the SN1 reaction is not a concerted reaction. In an SN1 reaction, the bond-breaking step occurs first, leading to the formation of a carbocation intermediate, followed by the bond-forming step with the nucleophile. Therefore, SN1 is the correct answer as it does not fall under the category of concerted reactions.

8. Which one do you like?

Option 1

Option 2

Option 3

Option 4

The given question asks for a preference between four options. The correct answer is Option 1, indicating that the person likes Option 1 the most out of all the given options.

Explanation

The given question asks for a preference between four options. The correct answer is Option 1, indicating that the person likes Option 1 the most out of all the given options.

9. Mercaptans can be produced by photochemical addition of ______ to alpha olefins.

Hydrogen sulphide

Sulphur

Hydrogen

Paraffins

Mercaptans are organic compounds that contain a sulfur atom bonded to a hydrogen atom. In the given question, it is stated that mercaptans can be produced by photochemical addition. This process involves the combination of two substances through a photochemical reaction initiated by light. Among the options provided, hydrogen sulfide (H2S) is the most suitable compound for this reaction as it contains both hydrogen and sulfur, which are necessary for the production of mercaptans. Therefore, hydrogen sulfide is the correct answer.

Explanation

Mercaptans are organic compounds that contain a sulfur atom bonded to a hydrogen atom. In the given question, it is stated that mercaptans can be produced by photochemical addition. This process involves the combination of two substances through a photochemical reaction initiated by light. Among the options provided, hydrogen sulfide (H2S) is the most suitable compound for this reaction as it contains both hydrogen and sulfur, which are necessary for the production of mercaptans. Therefore, hydrogen sulfide is the correct answer.

10. The reactions which are caused by heat and in absence of light is called _____

Photochemical reactions

Dark reactions

Reversible reaction

Reversible photochemical reaction

Dark reactions are the correct answer because they refer to chemical reactions that occur in the absence of light. These reactions are typically driven by heat or other forms of energy, rather than by light. Dark reactions are an important part of photosynthesis, where they take place in the stroma of chloroplasts and convert carbon dioxide into glucose using the energy stored in ATP and NADPH, which are produced in the light-dependent reactions.

Explanation

Dark reactions are the correct answer because they refer to chemical reactions that occur in the absence of light. These reactions are typically driven by heat or other forms of energy, rather than by light. Dark reactions are an important part of photosynthesis, where they take place in the stroma of chloroplasts and convert carbon dioxide into glucose using the energy stored in ATP and NADPH, which are produced in the light-dependent reactions.