A close-up image of a graduated cylinder shows the meniscus at the 24.6 mL mark. What is the correct reading for the volume, using the appropriate number of significant figures?

• A. 24.60 mL
• B. 24.7 mL
• C. 24.6 mL
• D. 25 mL

Answer: (C)

Verified step by step guidance

1. Understand that when reading the volume from a graduated cylinder, you must estimate one digit beyond the smallest marked division to reflect the precision of the measurement.
2. Identify the smallest marked division on the graduated cylinder. For example, if the markings are every 1 mL, then you estimate to the nearest 0.1 mL.
3. Look at the meniscus, which is the curved surface of the liquid. The correct volume reading is taken at the bottom of the meniscus at eye level.
4. Since the meniscus is at the 24.6 mL mark, and the smallest division allows estimation to the tenths place, the volume should be recorded as 24.6 mL, reflecting the correct number of significant figures.
5. Avoid rounding to 24.60 mL or 25 mL unless the instrument's precision supports those digits; 24.6 mL is the most accurate and appropriate reading here.