Purpose of the experiment:
The purpose of this lab is to help understand how to resolve the density of liquids and solids. Also, the lab is supposed to teach us how to record lab data and how to measure volume and mass the correct way. Lastly, it’s designed to help us understand significant values and its relationship to measurements and data recording.
One technique that will be used during this lab is comparing the accuracy (absolute & percent errors) of your calculated densities to accepted literature values.
Also, learn how to determine the precision for each of your measurements and compare results. We will find out the density of water, hexane, zinc, lead, copper and know which is the densest compared to the others.
1. Obtain the mass of your 100-mL graduated cylinder. Make sure it is dry before you weigh it out.
2. Add 20-25 mL of distilled water to the graduated cylinder. Measure the volume of the water very carefully.
After: Measure the combined mass using an electronic balance.
3. Add another 20-25 mL of distilled water to the graduated cylinder. Measure it carefully.
4. Repeat step 3 to obtain a third set of mass and volume measurements.
5. Use a thermometer to record the temperature of the water in your graduated cylinder.
Analysis: Subtract the mass of the empty cylinder from each combined mass measurement to obtain three mass measurements of water. Take the average of these three density values and look up the TRUE density of water at the temperature used. Evaluate the accuracy of your average density by calculating your percent error.