Understanding the Ideal Gas Law through Lab Experimentation

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Introduction
The goal of this lab is to apply principles of the ideal gas law to solve for n or the number of moles carbon dioxide produced, and compare the amount found using the ideal gas law to the actual amount. In order to complete this lab it's necessary to understand the apparatus below. By filling the Erlenmeyer flask completely full with water the mass of CO2 gas in the top of the flask can be determined. Since the combination of sodium bicarbonate and oxalic acid produces CO2 gas, this gas then moves from the gas generation bottle into the tube connected to the pneumatic trough. This gas then moves through the hole in the trough into the Erlenmeyer flask. The gas rises to the top and then pushes the water down and out. By measuring …show more content…

Calculate the average gas volume produced.

(325 mL + 219 mL) = 272 mL 2
3. Use Dalton’s Law of Partial Pressures to calculate the pressure with respect to only the carbon dioxide. Record the carbon dioxide pressure.

749 mmHg - 22.1 mmHg = 726.9 mmHg = 727 mmHg 4. Use the ideal gas equation, to solve for the number of moles of carbon dioxide produced. Remember that variables in this equation must have units of atm, L, and K. Also R = 0.0821 Latm/molK. Also, since you are interested in moles of CO2, use the CO2 pressure. Show your work for any conversions made in addition to your working for solving for moles. Record the number of moles of CO2. PV=nRT (0.956579 atm)(0.272 L) = n (0.0821)(295.8 K)
P = 727 mmHg ÷ 760 mmHg = 0.956579 atm (0.260189) = n (24.2852)
V= 272 mL ÷ 1000 mL = 0.272 L n = 0.0107 mol
T= 22.8oC + 273 = 295.8 K
5. Calculate and record the mass in grams of carbon dioxide produced. Convert moles to grams.

0.0107 mol = g ÷ 12.01 + 2(16.00)
0.0107 mol = g ÷ 44.01
0.0107 mol ÷ 44.01 = g g = 0.471 …show more content…

By dividing the 0.471g (experimental value) by 0.599 g (actual value) and multiplying by 100 the percent recovered was found to be 78.6%. Since the percent recovered was less than the actual value the experiment lost some of the CO2 in the process. This means that the combination of human and experimental errors affected the results. One of the major experimental errors is knowing when the reaction between the sodium bicarbonate and oxalic acid is completed. By putting the stopper in the Erlenmeyer flask too soon not all of the gas will have made it into the flask. Additionally since we were using tap water the density is slightly off that of pure water. This slightly alters CO2 ability to take up space in the flask. The combination of these factors accounts for the percent lost in the

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