Problem 110 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the following: List I List II 1\. Iodoform (i) Anaesthetic 2\. Methyl salicylate (ii) Antiseptic 3\. Diethyl ether (iii) Insecticide 4\. Hexachlorocyclohexane (iv) Detergent (v) Pain balmThe correct matching is: \(\begin{array}{llll}1 & 2 & 3 & 4\end{array}\) (a) (i) (iv) (ii) (v) (b) (iii) (iv) (i) (ii) (c) (ii) (v) (i) (iii) (d) (v) (iv) (i) (iii)

Step-by-Step Solution

Answer

The correct matching is option (c).

Step 1: Analyze the Chemical Properties

Let's begin by understanding the functionalities associated with each item on List I: 1. Iodoform is known for its antiseptic properties. 2. Methyl salicylate is commonly used in topical pain relief balms. 3. Diethyl ether is a well-known anaesthetic due to its properties as a general anesthetic. 4. Hexachlorocyclohexane (HCH) is an insecticide, commonly known as Lindane.

Step 2: Match Each Item

Using the properties identified in Step 1, we will match them with items in List II: 1. Iodoform matches with (ii) Antiseptic. 2. Methyl salicylate matches with (v) Pain balm. 3. Diethyl ether matches with (i) Anaesthetic. 4. Hexachlorocyclohexane matches with (iii) Insecticide.

Step 3: Confirm the Correct Option

Now we confirm the correct option using the matches we've identified: 1. Iodoform - (ii) Antiseptic 2. Methyl salicylate - (v) Pain balm 3. Diethyl ether - (i) Anaesthetic 4. Hexachlorocyclohexane - (iii) Insecticide This matches perfectly with option (c).

Key Concepts

Iodoform as an Antiseptic

Iodoform is a yellowish solid compound with distinct antiseptic properties. It has been used for its disinfectant qualities since the 19th century, especially in medical and surgical settings. Iodoform releases iodine slowly, which is key to its effectiveness in killing bacteria and preventing infection.
When applied to wounds, iodoform helps in cleansing the area and reducing microbial presence. This usage is crucial in preventing the onset of infections which can complicate wound healing.

• Iodoform is particularly noted for its use in minor surgeries and for treating wounds and ulcers.
• Its antiseptic property is due to the iodine released, which disrupts the cell walls of microorganisms.

Despite its benefits, iodoform has a strong, distinctive odor, which sometimes limits its use. Nevertheless, in its time, it was one of the few antiseptics available with significant efficacy.

Methyl Salicylate in Pain Relief

Methyl salicylate is an organic ester naturally produced by many species of plants, and it's commonly known for its minty aroma. Also referred to as oil of wintergreen, this compound is extensively used in pain relief balms. When applied to the skin, methyl salicylate acts as a counter-irritant.
The compound produces a sensation of warmth which helps to distract from the underlying pain or discomfort. This effect, combined with its ability to penetrate the skin, makes it effective in providing relief from muscle and joint pains.

• Methyl salicylate is commonly used in formulations for muscular strains and arthritis pain relief.
• It functions by stimulating blood flow to the affected area, enhancing its soothing effect.

Care should be taken during application as excessive use can lead to skin irritation or sensitivity reactions.

Diethyl Ether as an Anaesthetic

Diethyl ether, a highly volatile and flammable liquid, was one of the first substances used as a general anesthetic. Its introduction revolutionized surgery by enabling more complex operations to be performed without pain. Diethyl ether's anesthetic qualities stem from its ability to depress the central nervous system, rendering the patient unconscious during surgery.
Despite its effectiveness, diethyl ether has largely been replaced by other anesthetics due to its pungent odor and potential for postoperative nausea.

• The compound is typically administered by inhalation, allowing for quick onset of anesthesia.
• It was particularly renowned for its reliability and minimal side effects when used correctly.

The historical significance of diethyl ether in medical practices cannot be overstated, marking a transition into modern anesthetic techniques.

Hexachlorocyclohexane as an Insecticide

Hexachlorocyclohexane, hexachloran, or Lindane, is known for its insecticidal properties and has been widely used in agriculture to control insects on crops. This compound interacts with the nervous system of insects, interfering with nerve signal transmission and ultimately leading to their death.
Due to its effectiveness, it became a staple in pest management practices for several decades.

• Its use spans applications in both agricultural settings and public health schemes to combat lice and scabies in humans.
• However, environmental concerns about its persistence and potential biological accumulation have led to strict regulation.

Hexachlorocyclohexane's use is significantly reduced in many countries, owing to its environmental impact, but its role in historical pest control practices remains significant.