Gulp Lab

Jared Fischler

2/7/2012

Purpose: To determine number of atoms in a gulp of water

Materials Plastic cups Water Triple-beam balance Calculator Mouth

Procedure1. Gather safety gear2. Gather materials3. Fill a cup about ¾ with water4. Measure the mass of the cup with water to .001g5. Take one gulp of water6. Measure th mass of the cup after one gulp is taken7. Find the difference of the two masses to find the mass of your gulp8. Calculate the molar mass of water and use the molar roadmap to find the amount of atoms in

your gulp. 9. Repeat steps 3-8 3 times with a clean cup every time10. Collect all data in data table11. Calculate percent and relative error

Data

Mass before gulp

Mass after gulp

Difference in mass

Atoms

Trial 1 139.000g 116.723 22.277 2.035x10^24

Trial 2 96.012 76.999 19.013 1.909x10^24

Trial 3 108.701 85.769 22.932 2.302x10^2

4

Relative Error

((22.932g-19.013g)/21.407g)*100

=18.307%

Average Gulp

=21.407g

Average atoms

1.809x10^24

Percent Error

(abs(21.407g-47.544g))/47.544g)*100

=54.97% Accepted Value

=47.544g

Sources of ErrorOur gulps of water were difficult to keep the same, which resulted in very varied data. This really

skewed our results as is obvious from our error calculations. The accepted value was also not extremely reliable because it was based off of the class average gulp. Many kids were purposefully taking gulps much larger than normal gulps which made the value not as reliable as an accepted value should be.

ConclusionAfter observing my data and observations, I conclude that my average gulp contained around 1.809x10^24 atoms. The lab as a whole was not entirely reliable because of the difficulties that come with measuring something such as a gulp of water (as shown in the error calculation results), but it was reliable enough to show about how many atoms in an average gulp of water.