You can leave a response, or trackback from your own site. You can follow any responses to this entry through the RSS 2.0 feed. This entry was posted on at 10:33 am and is filed under Uncategorized. I’m not sure what my problem is with lab glassware. I mean, I don’t forget that my coffee cup is called a coffee cup. Wikipedia says it’s also called a conical flask, but I’ve never heard it called that. Only a fool wouldn’t know the difference between a flask and a beaker! GOSH. I was more focused on this really important problem with the data. When the container issue arises, I mumble my way through it. This is a confession I could never make to my colleagues. and I still have a difficult time remembering which is which. I have been doing science in one way or another for almost twenty years now…. At any rate, usually those containers are flasks or beakers, occasionally a graduated cylinder. At this moment, I can’t think why the container would ever be germane to a conversation… but you’d be surprised. It is also good for mixing and heating.There have been many moments in my life when I am describing something I’ve done in the lab and I come to the point wherein I am describing the container I used. If volume only had to be estimated, a flask would be OK. I would not use a flask to measure volume given the large percent error. The beaker is pretty accurate, and you can easily stir and heat chemicals in it. If you need to measure other volumes besides those on volumetric flasks, then the graduated cylinder is the best tool. The volumetric flask is the most accurate, but it only measures 1 volume-in this case, 100mL. For example, which pieces should be used for measurement, and which should not be used for measurement? The second method was more precise because volume was calculated using density, the temperature of water, and a digital balance.īased on accuracy, assign each piece of glassware appropriate uses and state evidence for your choice. The first method provided a less precise ranking of glassware since the volume of water had to be estimated for every piece of glassware but the volumetric flask. How do the 2 methods of determining accuracy compare? Were the results the same or different? The flask had the highest percent error (17.4%), so it is the least accurate. Both were small, so they are fairly accurate. The graduated cylinder and beaker were similar in percent error (2.2% and 3.5% respectively). The volumetric flask had the lowest percent error (0.3%), so it is the most accurate. Volumetric flask, graduated cylinder, beaker, flask GlasswareĬalculate the percent error for each piece of glassware and record the values.īased on percent error only, rank the glassware from most accurate to least accurate. (Handbook of Chemistry and Physics, 53rd Edition)Īverage the individual actual volumes for each piece of glassware and place the values in the table. Using individual data and the density of water table, calculate the actual volume of water in each piece of glassware.ĭensity = mass/volume Density of Water by Temperature Student answers will vary, but they should notice higher accuracy for the volumetric flask and graduated cylinder. Based on the data collected, rank the 4 pieces of glassware from most accurate to least accurate.
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