Chemistry Lab

Chemistry Lab

Density of a liquid

Nour Hegazy

Grade: 10T

Pre-lab Questions:

1) Why are we measuring the density of a liquid using three different techniques?

To concluded which method is more accurate.

2) Is density an extensive or intensive property? Explain your answer.

Density is an intensive property, because density does not depend on the amount of substance present.

Methods used to measure the density of liquids: A, B, and C.

Method A:

Transfer 25 cm cubed of the unknown liquid into the second beaker using pipette. Weigh the second beaker using a balance, then record the mass onto your lab sheet.

Method B:

Using a clean and dry graduated cylinder, measure out 25 cm cubed of the unknown liquid into the first beaker. Determine the mass by weighing the graduated cylinder with the unknown liquid inside of it using a balance. Record the mass onto your lab sheet.

*Repeat Method A and B with liquid A,B and C. All results must be recorded onto lab sheet.

Results (Mass of liquids):

Finding the density:

Divide the mass of each liquid by the volume (25 cm cubed) to determine the density of each unknown liquid.

Results (Density of liquids):

Post-Lab questions:

1-What is the quickest method for determining the volume of a liquid? Which is the most accurate?

Method B was the quickest, since the pipette was not as easy as simply pouring 25cm cubed of an unknown liquid into a graduated cylinder. The pipette even though fast, was a bit confusing at times; since it was our first time using a pipette. The most accurate method would have to be method B since the graduated cylinder is very accurate concerning numbers. As for the second beaker; it was only marked with the 30 cm cubed, even though the pipette had a mark to show 25 cm cubed, method A had both beakers marked with numbers; therefore making method B more accurate.

2- How do your densities compare with the two methods of volume determination for the liquid?

The