Chemistry In Everyday Life

The given reaction involves the base-catalyzed (NaOH) decomposition of 1-phenylethanol (Ph-CH(OH)-CH ) under heating ( ). This leads to two main products through different pathways:
Product 1: Acetophenone (Ph-CO-CH )
- Formed via oxidation of the alcohol
- The base abstracts a proton from the -OH group
- Resulting in formation of a carbonyl group
Product 2: Styrene (Ph-CH=CH )
- Formed via elimination reaction
- NaOH abstracts a proton from the β-carbon
- Leads to formation of a double bond Mechanistic pathways:
1. Oxidation pathway:

2. Elimination pathway:

Why not other options?
- Only these two major products form under these conditions
- No significant side products are expected
- The reaction doesn't proceed to complete decomposition

1. Analgesics ----- molecular targets: Analgesics are primarily classified by their effect in relieving pain rather than specific molecular targets. Therefore, this classification does not accurately match.
2. Sulphonamides ----- drug action: Sulphonamides, which are antimicrobial agents, are typically classified by their mechanism of action, not just their action, making this a partial mismatch.
3. Antihistamines ----- chemical structure: Antihistamines are grouped by their ability to block histamine at its receptors rather than simply by their chemical structure. Thus, this is not the correct classification criterion.
4. Antiseptics ----- pharmacological effect: Antiseptics are substances that inhibit the growth and development of microorganisms on living tissues, classified based on their pharmacological effect. This classification is correct.

Solution:

The given problem is to match elements to their corresponding categories correctly based on the provided options. We need to identify the suitable pairs from:

Based on the information provided, the correct match is . This indicates that:

• The element or compound labeled as A corresponds to category II.
• The element or compound labeled as B corresponds to category III.
• The element or compound labeled as C corresponds to category I.

To validate the solution, closely examine the properties or specifics of each element, ensuring logical matching to each numbered category in accordance with standard chemical classifications or characteristics.

The reactions that result in the formation of phosphine (PH₃) are analyzed below:

1. Reaction of calcium phosphide (Ca₃P₂) with water:
   This reaction yields phosphine and calcium hydroxide:
   
   Thus, option (i) produces phosphine.
2. Heating white phosphorus (P₄) with concentrated NaOH solution in an inert atmosphere:
   This reaction generates phosphine:
   
   Therefore, option (ii) also leads to phosphine formation.
3. Heating red phosphorus with alkali:
   This reaction does not produce phosphine under normal conditions; instead, phosphite salts may form.
   Hence, option (iii) does not give phosphine.

From the options analyzed, the reactions that give phosphine are i and ii only.

The correct answer is: