Mixture density calculation

Steps:

• Mass of glycerine: 1.3 g cm⁻³ × 40 cm³ = 52 g
• Let V = volume of water (cm³); mass of water = 1.0 g cm⁻³ × V = V g
• Total mass = 52 + V g; total volume = 40 + V cm³
• Density equation: (52 + V) / (40 + V) = 1.1 → solve: V = 80 cm³

Why D is correct:

• 80 cm³ satisfies the density formula, giving total mass 132 g in 120 cm³ for exactly 1.1 g cm⁻³.

Why the others are wrong:

• A: 40 cm³ yields (52 + 40) / 80 = 1.15 g cm⁻³, higher than 1.1
• B: 8 cm³ yields (52 + 8) / 48 = 1.25 g cm⁻³, much higher
• C: 34 cm³ yields (52 + 34) / 74 ≈ 1.16 g cm⁻³, higher than 1.1

Final answer: D