Draw the electron dot structure of:

(a) Methane molecule

(b) Nitrogen molecule

[Atomic number: N = 7, C = 6, H = 1]

Complete and balance the following equations:

(a) Al₂O₃ + 2NaOH ⟶

(b) C₂H₅COONa + NaOH $\overset{\text{Δ}}{\underset{\text{Cao}}{\longrightarrow}}$

(c) C₂H₄Br₂ + alcoholic KOH $\overset{\text{Δ}}{\longrightarrow}$

Name the main metal used in making of the alloys given below:

(a) Duralumin

(b) Stainless steel

Differentiate between the following pairs based on the criteria given:

(a) Sulphuric acid and Nitric acid (using barium chloride solution)

(b) Unsaturated and Saturated hydrocarbons (type of bond present)