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Its 10 ml graduated cylinder with 25 ml of pycnometer, and we are measuring the density of the liquid(pure liquid) in each of the materials and we are suppose to compare the densities found , in terms of accuracy

Excuse me guys am doing a a research project on density, these are the two methods i used to find the accuracy, been searching but i have no progress. Feel free to give suggestions.

Georgy
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    Please improve your question with more details. I know what a pycnometer is, and how it is used. But what do you mean by a cylinder, and how do you use it? Also are you trying to determine the density of solids or liquids? – MaxW Mar 13 '19 at 17:30
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    And what are you aiming for in this (educational?) project? – Karl Mar 13 '19 at 18:57
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    @MaxW, yes its 10 ml graduated cylinder with 25 ml of pycnometer, and we are measuring the density of the liquid in each of the materials and we are suppose to compare the densities found , in terms of accuracy. the graduated cylinder was weighed and 1 ml of water is added respectively till the 10 ml mark is reached, its masses were recorded. – Georgy Mar 14 '19 at 02:12
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    @Karl, the aim of this project is to find the liquid density of the pure liquid using a 25 ml pycnometer and graduated 10 ml cylinder and compare their densities interms of accuracy – Georgy Mar 14 '19 at 02:16

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Cylinder is always a "secondary standard" in volumetric measurements. It is never used in quantitative transfers. A pycnometer is designed to hold known volumes and it should always be used for density measurements at known temperature. Good quality pycnometers come with a certificate of quality assurance.

If you are interested in a deeper investigation, analytical glasswares come in two grades, Class A and Class B defined by so-called tolerances by various organizations. If you look closely you will see these labels on quality glassware. Similarly, look for TD and TC label on cylinders and other volume measuring glasswares. TD means to deliver and TC means to contain. If you don't see any A or B label, chances are that this glassware just good for educational purposes (or economical version). European union and other countries have set limits on volumetric accuracy.

AChem
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    A bit less accurate than a pycnometer, but much cheaper, are https://en.wikipedia.org/wiki/Volumetric_pipette s. I'm happy to say my university never insulted us with cheap, lower grade glassware. ;-) – Karl Mar 14 '19 at 19:43