Lab 1A: Density Block Lab

Introduction:

The purpose of this lab is to determine the mass of a plastic block using its density and volume.  My partner and I calculated the mass of the block using the calculated volume and the given density of the block.  Afterwards, we found the actual mass by weighing the block on a scale, and calculated the percent error using the percent error formula.  Important terms include density (mass per unit volume of an object), mass (the amount of matter in an object), and volume (the amount of space an object occupies).

Procedure:  

First, we used a ruler to carefully measure each side of the plastic block --- length, width, and height.  We then calculated the volume by multiplying the three numbers.  Afterwards, we plugged the volume and density of the block (which was already given to us) into the D=M/V equation to find the mass.  To determine whether our calculation was accurate or not, we weighed the block on a scale. Finally, using the percent error formula, ((actual - experiment)/actual) x 100%, we found the percent error.

Data:  

Block:

• height - 1.25 cm
• length - 9.33 cm
• width - 6.82 cm

Volume: 82.1 cm^3

On our first try, we calculated the mass to be 44.4 grams using the D=M/V formula.  82.1 cm^3 was the volume, and the given density was 0.541 g/cm^3.  The block was actually 44.5 grams, leaving a percent error of 0.225%.

Conclusion: 

We successfully fulfilled the purpose of the lab on our first try.  We learned that we had to be very precise when measuring objects with a ruler, and some sources of error include inaccuracy with measuring and rounding to significant figures.  In the future, to prevent the same errors and improve the accuracy of our results, we would need to pay closer attention to significant figures and rounding.