Explanation

Percentage yield = (Actual / Theoretical) × 100  

= (20 / 25) × 100 = 80%

Explanation

- 1 mol of any gas at STP occupies 22.4 dm³  

- 1 mol H₂ gives 1 mol H₂O → 22.4 dm³ H₂ required

Explanation

 sp³ has 25% s-character → largest  

- sp² has 33% s-character  

- sp has 50% s-character → smallest  

More s-character means smaller orbital.

Explanation

Benzene is aromatic, stable, follows Hückel’s rule (4n+2 π electrons), but it is not highly reactive due to resonance stabilization.

Explanation

Benzene is aromatic, stable, follows Hückel’s rule (4n+2 π electrons), but it is not highly reactive due to resonance stabilization.

Explanation

UV light or heat is required to initiate the formation of free radicals by homolytic cleavage of the halogen molecule (e.g., Cl₂ → 2Cl•).

Explanation

- Buffer reaction: NH₄⁺ + OH⁻ ⇌ NH₄OH  

- Adding H⁺ reacts with OH⁻ to form water, reducing OH⁻ concentration.  

- To restore balance, the equilibrium shifts forward to produce more OH⁻, neutralizing added H⁺.

Explanation

A basic buffer consists of a weak base and its salt.  

- NH₄OH is a weak base; NH₄Cl is its salt.  

- So, NH₄OH/NH₄Cl is a basic buffer.

Explanation

- According to the ideal gas law, at absolute zero, temperature = 0 K.  

- Pressure is proportional to temperature (P ∝ T).  

- So, pressure (P) = 0 atm at −273°C.

Explanation

- PVC is made from repeating vinyl chloride monomers (all the same type).  

- It softens on heating and can be reshaped.  

- Hence, PVC is a thermoplastic polymer.