Which of the following apparatus can be used to measure a specific volume of a liquid accurately?

Analyze the question: You need an apparatus that measures a specific (fixed) volume of liquid accurately. The key words are "specific volume" and "accurately".

Explain the concept: Laboratory glassware differs in precision:

• Beaker: Used for holding, mixing and heating liquids. Its markings are only rough estimates, so it is not accurate.
• Conical flask: Used for titrations, mixing and swirling. Its markings are also approximate.
• Measuring cylinder: Measures variable volumes with moderate accuracy. It is good for general use but not the most precise.
• Pipette: Designed to deliver one fixed, exact volume (e.g. 20.0 cm³ or 25.0 cm³) with high accuracy. This is why it is used in titrations to measure the acid or base solution.

Solution:

1. Eliminate A and B, since they are not measuring instruments for accurate work.
2. Compare C and D. A measuring cylinder can measure different volumes, but with less precision.
3. A pipette is calibrated to deliver a specific volume very accurately, which matches the wording of the question.

Answer: D. Pipette

Exam tip: Remember the order of accuracy: Beaker < Measuring cylinder < Pipette/Burette. Use a pipette for a fixed volume and a burette for variable volumes delivered accurately, such as in titration. When you see "specific volume" and "accurately," think pipette.