Ideal Gas Constant

Determination of Gas Constant R

Student name: Peter S. Byun
Course; IB Chemistry SL1

Purpose:

The purpose of this experiment is to use a eudiometer to determine experimentally the gas constant value R.

Data Collection and Processing:

Table1: Quantitative Data collected throughout the experiment.
| Trial 1 | Trial 2 | Trial 3 |
Mass of magnesium/g (±0.005) | 0.03 | 0.03 | 0.03 |
Water depth/mm (±0.1) | 70 | 70 | 70 |
Volume of H2 gas collected/L (±0.00005) | 0.0254 | 0.0506 | 0.0514 |
Pressure of water liquid/kPa (±0.5) | 0.686 | 0.686 | 0.686 |
Pressure of water vapor/kPa | 3.2 | 3.2 | 3.2 |
Pressure of hydrogen gas dry/kPa (±0.5) | 98.8 | 98.8 | 98.8 |
Room temperature/℃ (±0.05) | 23.9 | 23.9 | 23.9 |
Constant R/LkPaK-1mol-1 | 8.312381 | 8.313808 | 8.312476 |
Percent Error/ % | 0.02515 | 0.00799 | 0.02401 |

Qualitative Data collected throughout experiment

1.   When the eudiometer was reversed and fixed onto the ring stand, hydrochloric acid slowly descended and mixed with the deionized water.
2.   As the magnesium ribbon reacted with HCl, tiny bubbles formed around the copper tied around the magnesium.
3.   As the reaction proceeded, the bubbles grew bigger and floated upward.
4.   The reaction happened even faster and more rigorously as it reached the climax. Bubbles formed one after another and shot upward in a zigzag motion.
5.   While the reaction happened, MgCl2 was created and flowed downward. This then sank to the bottom of the beaker. The seemingly oily substance was not soluble, for difference between the substance and deionized water was visually comparable.
6.   The formation of bubbles suddenly reduced in size and amount and when almost all of the reaction lessened.
7.   Even after the complete dissolution of the magnesium ribbon, the colorless substance continued to move around the burette, and flowed out of the burette into the beaker.
8.   Miniscule bubbles stuck to the copper either floated upwards....