Question

When you read the syringe, keep the following points in mind:

The syringe will be upside down.

The numbers increase upward even though the numbering may be upside down.

Estimate the one significant figure beyond the graduations shown.

The best reading for the volume of the gas in the syringe in the picture shown right is

Answer 1

I don’t see the picture — could you either attach it or describe exactly where the plunger tip lies relative to the nearest markings (e.g., “between 3 and 4 mL, about one-quarter of the way from 3 toward 4”)? Then I’ll give the best reading.

Meanwhile, here’s how to get the correct answer yourself:

1. Remember the syringe in the photo is upside down, so treat the numbers as increasing upward (toward the needle end).
2. Identify the plunger tip (the flat/rubber end that seals the barrel). For a gas in a syringe you read the position of that plunger tip, not a liquid meniscus.
3. Find the nearest lower graduation (a whole mL mark, usually) and the next higher one.
4. Estimate one significant figure beyond the smallest graduation shown (if graduations are 1 mL, estimate to 0.1 mL; if 0.2 mL graduations, estimate to 0.02 mL, etc.).
5. Report the reading with the proper number of significant figures (for 1 mL graduations, e.g. 3.2 mL).

Example: if the plunger tip is between 8 and 9 mL and appears about 80% of the way from 8 toward 9, read ~8.8 mL. Upload the image or a description and I’ll give the specific value.