Density Determinations Lab, Lab Report Example

Introduction

The aim of this experiment is to determine the density of a known material based on awareness of the object’s known mass and volume. This is helpful because it allows us to confirm the identity of materials, and infer other properties about it, such as its melting point and boiling point. Knowledge of this is particularly useful in construction applications. The density law states that density is equivalent to the mass divided by volume. When one of these values are unknown, the third can be calculated. Mass is defined as the amount of matter an object has, while the volume is defined as the amount of physical space it occupies.

Materials and Procedures

To conduct this experiment, an unknown liquid sample, regularly shaped and irregularly shaped metal samples, and sodium chloride were used. The regularly shaped metal was measured using a ruler to determine its volume and then weighed to determine its mass. The irregularly shaped metal was inserted into a graduated cylinder containing water to determine the volume and then weighed to determine its mass. Their density was then calculated using these values and the density equation. Next, this process was repeated to determine the density of water. Lastly, sodium chloride solutions were made at various dilution levels and this process was repeated for solutions with sodium chloride percentages between 5% and 25%.

Results

Table 1 Report of the results

All densities were calculated by performing density = mass/volume. For example 47.278g/1mL=47.278g/mL, which indicates the density of the solid. Second, 19.520g/20mL=.976g/mL, indicating the density of the liquid. None of the data should be eliminated. The calculated volume of the water is close to the expected calculation of 1g/mL. Any results that varied compared to classmates were likely due to human error as a consequence of imprecise reading of the measuring equipment. Next time, I would read the ruler and graduated cylinder values several times and average them together to ensure that my readings are maximally accurate.

Conclusion

This lab indicated that density could be calculated once the mass and volume of an object are known. The mass and volume of these objects can be determined by using simple measurement tools such as rules and graduated cylinders. This lab helped prove that the density of water is equal to or close to 1 g/mL. There is a 99.024% error, indicating that this value is reliably accurate. If this experiment were to be completed again, I would take greater care to ensure that the measurements are correct. This could be done by using more precise measurement tools or by taking several measurements and then averaging them together. It is likely that the density measurements that are considered standard were acquired by making a series of many measurements across many individuals and instruments to confirm the accuracy and precision of this number, and this is what would need to be done to ensure that the calculated density of any true unknowns is accurate. It is important for this information to be correct because other scientists will rely on the value of this number for a variety of purposes.