4 public questions tagged with this topic.
Moles of NaOH = (4/40) = 0.1 mol . Molarity = (Moles/Volume in L) , so 0.5 = (0.1/V) . Volume = (0.1/0.5) = 0.2 L = 200 mL . Since total volume is 200 mL, water volume = 200 mL (assuming solute volume is negligible).
Ref: NCERT Class 12 Chemistry > Chapter 1: Solutions > Topic: Vapour Pressure and Raoult's Law - Ideal and Non-ideal Solutions
Moles of NaOH = (4/40) = 0.1 mol . Volume = 250 mL = 0.25 L. Molarity = (0.1/0.25) = 0.4 M .
Ref: NCERT Class 12 Chemistry > Chapter 1: Solutions > Topic: Colligative Properties - Relative Lowering and Elevation of Boiling Point
Mass of 1 L solution = 1000 × 1.04 = 1040 g. Mass of NaOH = 1 × 40 = 40 g. Mass of water = 1000 g = 1 kg. Molality = 1/1 = 1 m.
Ref: NCERT Class 11 Chemistry > Chapter 1: Some Basic Concepts of Chemistry > Topic: Reactions in Solutions and Mass Percentage and Numericals
13 accurately defines or describes the concept asked in this question. Within pH and Buffer, precise definitions and terminology are essential for clear scientific communication. The other options (12, 14, and 15) either describe related but distinct concepts, use incorrect terminology, or confuse similar-sounding terms that have different scientific meanings. A thorough understanding of exact definitions helps distinguish between closely related biological concepts and is crucial for competitive examinations.
Ref: Lehninger Principles of Biochemistry, Nelson & Cox, 8th Ed., Ch. 2
