When primary alcohol reacts with a strong oxidizing agent then an acid is formed as a product. When primary alcohol reacts with the mild oxidizing agent then aldehyde is formed as a product. 

Here, CrO₃ – H₂SO₄, K₂Cr₂O₇ + H₂SO₄, and KMnO₄ + KOH/H₃O⁺ are strong oxidizing agents thus, converts alcohol into acid. 

But Cu, 573 K, and CrO₃₊ (CH₃CO)₂O are the weak oxidizing agent and reduce primary alcohol to aldehyde. 

Thus, option third is the correct answer. 
 

When ether reacts with HI then cleavage of the ether bond takes place. The mechanism of the given compound is as follows:

Here, phenol and benzyl iodide are formed as products. 

The correct answer is option fourth.

The rate of dehydration reaction depends on the stability of carbocation. The stability of carbocation is as follows:

3^o > 2^o > 1^o 

The carbocation formed by the given compound is as follows: 

The carbocation formed in (iii) is the most stable because in (i), (iii), and (iv) carbocation is unstable because of -I effect of NO₂. Thus, option third is the correct answer. 
 

When alcohol reacts with HBr then substitution reaction takes place and the OH group is substituted by the Br atom. In the first step, the OH group is converted into an H₂O group, and a secondary carbocation is formed as a product. Then rearrangement of carbocation takes place and more stable tertiary carbocation is obtained. 
In the first step, tertiary carbocation reacts with bromide ion, and an alkyl halide is obtained as a product. 

The reaction with mechanism is as follows:

Thus, option second is the correct answer.

Explanation:

(1) “Lucas’ reagent” is a solution of anhydrous zinc chloride in concentrated hydrochloric acid. This solution is used to classify alcohols of low molecular weight. The reaction is a substitution in which the chloride replaces a hydroxyl group.

(2) Lucas reagent converts alcohols to alkyl chlorides: tertiary alcohols give an immediate reaction, indicated when the alcohol solution turns cloudy; secondary alcohols usually show evidence of reacting within five minutes; primary alcohols do not react to any significant extent. The order of reactivity of alcohols is: 

Among the given alcohols,  is a tertiary alcohol. So, it will react instantaneously with Lucas reagent. 

Thus, option 3 is the correct answer.

Regioselective

 Anti-Markovnikov 

(1) Five-membered ring

1. Tetrahydrofuran (THF)

• Type: Structural
• Achiral
  
  Count = 1

(2) Four-membered ring (Oxetanes)

2–3. 2-Methyloxetane

• Type: Optical isomers
• (R) and (S) forms
  
  Count = 2

4–5. 3-Methyloxetane

• Type: Optical isomers
• (R) and (S) forms
  
  Count = 2

(3) Three-membered ring (Epoxides / Oxiranes)

6–7. 1,2-Epoxybutane (Butylene oxide)

• Type: Optical isomers
• (R) and (S) forms
  
  Count = 2

8. 2,2-Dimethyloxirane

• Type: Structural
• Achiral
  
  Count = 1

9–10. 2,3-Dimethyloxirane

• Type: Geometrical + optical
• cis (meso) = 1
• trans (enantiomeric pair) = 2
  
  Count = 3

Final total:

Total = 10