Practice question

Given: How many molecules are in 4 g of H₂? (Molar mass = 2 g/mol, Avogadro number = 6.022 × 10²³) These values define the system as per NCERT data. Formula: Moles = 4 / 2 = 2 mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Molecules = 2 × 6.022 × 10²³ = 1.2044 × 10²⁴. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.