Explanation

Given:  

- Percentage yield = 80%  

- Actual yield = 20 g  

Formula:  

% Yield = (Actual Yield / Theoretical Yield) × 100

Rearranging:  

Theoretical Yield = (Actual Yield × 100) / % Yield  

= (20 × 100) / 80 = 25 g

Explanation

Fe: [Ar] 3d⁶ 4s²  

Fe³⁺ → loses 3 electrons → 3d⁵  

5 electrons in 3d → all unpaired → 5 unpaired electrons

Explanation

ΔU = q + w = 100 + 40 = +140 kJ

Explanation

Hydrogen gas reacting with chlorine to form hydrogen chloride gas  

This involves electron transfer: H is oxidized (loses electrons), Cl is reduced (gains electrons) → a classic redox process.

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•).