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#Molecular Mass

21 public questions tagged with this topic.

What is the mass of 5 × 10²³ molecules of CH₄? (Molar mass = 16 g/mol, Avogadro number = 6 × 10²³)

Given: What is the mass of 5 × 10²³ molecules of CH₄? (Molar mass = 16 g/mol, Avogadro number = 6 × 10²³) These values define the system as per NCERT data. Formula: Moles = 5 × 10²³ / 6 × 10²³ ≈ 0.8333 mol. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Mass = 0.8333 × 16 ≈ 13.33 g ≈ 13.3 g. 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.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom and Periodicity, Topic: Mole concept, atomic models and periodic trends.