Balance Lab Essay Example

was then subtracted from the combined weight resulting in the weight of the unknown slug by difference.

The slug was weighed by direct method by being placed directly on the electronic balance. Average mass of the 5 copper slugs was done by first weighing the first slug and recording the value, and repeating the steps each time a slug was added to the electronic balance. Then once all the slugs were added to the electronic balance the final value was divided by the number of slugs which in this case were 5 and the final value was the average weight of each copper slug.

Data: Centigram Balance direct weighing 1st Centigram Balance| Directly on 2nd Centigram balance| Slug: 2. 3g| 2. 6g|Centigram Balance by difference 1st Centigram Balance| Directly on 2nd Centigram balance| Beaker: 49. 2g| 49. 6g| Beaker w/slug: 52. 2g| 52. 2g| Beaker: 49. 6g| 3. 4g| Unknown mass Using Direct weighingBy difference Unk: 24. 72g| Beaker: 49. 6g| Null| Mass w/Beaker 74. 42g| | Calculated mass: 24. 82g| Average Mass of copper slugs 1 Slug: 2. 999g| | 2 Slugs: 6. 005g| | 3 Slugs: 8. 984g| | 4 Slugs: 11. 992g| | 5 Slugs: 14. 958g| | Average Mass of all slugs: 2. 9916g| | Solid Chemicals Centigram Balance| Electronic Balance| Watch glass w/sample: 10. 3g| 11. 100g| Watch glass: 9. 3g| 10. 000g|Sample by difference: 1. 0g| 1. 100g|

Results:

The data shown in the chart above is done by simple subtraction. The data was gathered by following the procedure and annotating the values as they read on both the electronic and centigram balances. The data is labeled as it

was retrieved following the procedure in the ChemLab program. All values are as they appeared on each perspective scale. Discussion & Analysis: All masses by difference were calculated by taking the mass of the slug and its container subtracted from the mass of the container with out the slug. This can bee seen in the example below.

Mass of beaker = 49.2g

Mass of Beaker & Slug= 52.2g.

Calculated mass of Slug= 3.0g 52. 2g – 49. 2g = 3.0g.

This same formula was applied to the rest of the measurements, although a different scale was used for some experiments although the values changed the formula stayed the same.

Conclusion

The purpose of this lab was to become familiar with what a Centigram Balance, Electronic Balance and High Sensitivity Balance was. Along with becoming familiar with the three different types of balances, the methods in which the mass of each item was to have it mass measured was also learned and understood.