The pressure of the water vapor was found on the chart that was given at the start of the lab, and the pressure correlated with the temperature of the water. The pressure of the water vapor was found by using the temperature of the water. When the mass of the sample was divided by the number of moles, a molar mass of 56. References: Chemistry by Zumdahl and Zumdahl, 6th ed. Use a sensitive balance to measure the mass of the empty test tube and foil. The second source of error is that little pieces of magnesium did not react with the hydrochloric acid in the position they were in.
Purity can be determined by identify the melting point. Next, we used a cork whose head was larger than the opening of the test tube to block off the opening without changing the pressure inside of the tube , so that we could transport the remaining water to a graduated cylinder. Ideal Gas Law Lab 1. Determine percentage error for your data. The pressure of the water vapor that corresponds with the water temperature of 23 degrees Celcius was 21 mm Hg. This was possible due to the assumption given in the beginning of the lab that the atmospheric pressure in the room is standard pressure. Thus, we recorded the gas pressure to be the same as the pressure in the room, which was calculated to be 763.
The opposite occurs as the butane is released. With the magnesium in the cage and the wire attached to the stopper, we put it in the tube. A substance having neither a fixed shape nor a fixed volume is a gas; gases assume both the shape and the volume of their container. The volume of hydrogen gas produced will be measured directly on the scale of a gas-measuring tube. The Gas constant we had a percent error of 7. The equations for determining the molar volume were extremely difficult for me and the first time I went through the lab I calculated a 93% and 78% error for trials 1 and 2 respectively. This assumption allowed one to use Dalton's Law of Partial Pressures which states that the pressure of the water vapor added to the pressure of the gas collected over the water is equal to the standard, or total, pressure.
Discussion: The molar volume of the H2 in our experiment is very close to the theoretical molar volume, but I think that the deviation lies in the temperature of the H2O: in the first trial it is too high and in the second one too low. Gases are constantly required by, and produced as a byproduct of, cellular and metabolic reactions, so an efficient system for their exchange is extremely important. However, because there is also water vapor, the gas in the tube contains both hydrogen gas and vapor. The molar mass of the chemical in this lab was 56. What is the percentage error between your value and 22.
A substance having a fixed volume and shape is a solid. Lower the stoppered end of the tube into the beaker of water. Make a small, needle-sized hole in the top of the tinfoil. The reaction that takes place in this reaction is a 1:1 mole ratio reaction. However, most of the gases encountered in the real world are real gases which do not strictly obey ideal gas laws.
After the calculations, I have evaluated the molar volume and density for trials one and two: 8. The molar mass of butane gas was calculated to be 56. The P in the equation is the pressure of the gas, the V is the volume of the gas, the n is the number of moles of gas, the R is the gas constant, and the T is the temperature of the gas in Kelvin. Procedure: First, we used a balance to weigh the canister of gas, and recorded that mass as the original weight. Since the stopper had a hole, we had to put a finger over it while turning it upside down and putting it in the beaker with water.
The molar mass of the butane gas was calculated by dividing the mass of butane gas in grams 0. To find out the purity of aspirin obtain by recrystallisation of prepared aspirin from reaction of salicylic acid with acetic anhydride. The measurements taken are then the corrected volume. Therefore P must be expressed in atmospheres atm , V in liters L , n in moles mol , and T in Kelvin K. We then filled a small test tube with water at the same temperature and poured that water into a graduated cylinder to measure the original volume of water in the tube. The graduated cylinder was filled to the brim and stoppered. To calculate the number of moles of the gas, the Ideal Gas Law, which states that the pressure of the gas multiplied by the volume of that gas is equal to the number of moles multiplied by the gas constant multiplied by the temperature in Kelvin, was used after the assumption that the gas behaved like an ideal gas was given.
Thus the number of moles of H2 can be determined if the number of moles of Mg is found. Wrap the piece of magnesium around the copper loop so that it will fit easily into the gas-measuring tube. Time Teacher preparation: 30 minutes Presentation: 30 minutes Several drying steps Class Time: 45 minutes Hazards Butane is flammable. By using the data gathered through the procedures and calculations above and the three assumptions given at the beginning of the lab, the number of moles of the gas was found, and the mass of the gas sample was calculated by finding the difference between the mass of the lighter before releasing the gas and after releasing the gas. The lighter is weighed both before and after the gas is withdrawn. Both are monosaccharides and with the same molecular formula C6H12O6 however, they are structural isomers as molecules are arranged differently in space this due to the glucose structure containing 4 chiral carbons and fructose containing 3 leading to stereoisomerism. You will make an experimental determination of the number of moles of hydrogen molecules produced and the volume occupied by these molecules.
Through this experiment my results in this experiment where not supported by the results we found. The difficulty of measuring the final volume meniscus - was the meniscus in the gas collecting tube could change do to where it was located if it where not water level. Gas shales are fine grained, organic rich sedimentary rock. Rodney Hahn May 6th Lab? The n was the number of moles of the gas. Distilled Water Helium H2O He 33. Measure and Record the length of a magnesium ribbon, Also record the mass of 1 meter of magnesium ribbon.