Gas Law Lab Report

In chemical reactions, the significance of knowing the limiting reactant is high. In order to increase the percent yield of product, increasing the limiting reactant, possibly, is the most effective. In this experiment we were able to calculate limiting reactants from the reaction of CaCl2. 2H2O + K2C2O4.H2O(aq).

The reaction you will be investigating is the reaction that occurs when an Alka-Seltzer tablet is placed into a given amount of water. Alka-Seltzer is an over-the-counter antacid and pain relief medication that is dissolved in water before it is ingested. Each tablet contains aspirin (acetylsalicylic acid), citric acid, and sodium bicarbonate. As the tablet dissolves in water, the bicarbonate ions in the tablet react with the hydrogen ions from the acids that are also contained in the tablet. The carbon dioxide gas produced by the reaction is what causes the bubbling that can be observed.

I took the graduated cylinder and started filling it up with water until the bottom of the meniscus was to the the 100.0 mL mark with the assistance of a dropper pipet. I then took the 13 x 100 mm test tube and slowly poured the water from the graduated cylinder into the test tube until it was full to the top. I then poured the water in the test tube out into the sink and put the graduated cylinder on the counter so I can get an accurate measurement of the lower meniscus to record on my data table. I once again followed the same procedure again filling a second test tube with water from the graduated cylinder then setting it on a straight surface to get an accurate measure of the volume to

Write a balanced chemical equation for the reaction of carbon dioxide with limewater. The formula for the active substance in limewater is on the pipet, and the products of the reaction are calcium carbonate and water.

1. Carefully measure the volume of the trapped gas using the graduations (markings) on the side of the container.

The goal of this lab was to determine the amount of grams of sodium bicarbonate (NaHCO3) required to produce enough CO2 gas to completely fill the lab and also how many Alka-Seltzer tablets that would equate to. This was done by collecting CO2 gas by inverting a buret and submerging it under water in order to calculate the volume of CO2 released from a fragment of Alka-Seltzer tablet. The main component of Alka-Seltzer is sodium bicarbonate, used to neutralize excess stomach acid during illness through the following reaction that generates CO2:

In this experiment the scientists are looking for how gas production is effected when different sized Alka-Seltzer tablets are put into water. The independent variable is the different sizes while the dependent variable is the amount of gas produced. A constant variable includes the same brand of Alka-Seltzer tablets, the volume of water and same starting temperature. Finally the scientist’s control variable is the first trial testing the whole tablet comparing its reaction time to each new piece.

9. How many moles of NaOH would be needed to completely react with all of the excess HCl determined in problem 8?

Alka Seltzer is a medical drug used for pain relief and used for relieving indigestion. For example, if you have a stomachache or some indigestion problems, Alka Seltzer may help neutralize the stomach acidity. Not only that, Alka Seltzer is also used for cleaning household items, such as vases or jewelry. Alka Seltzer contains citric acid and sodium bicarbonate, which makes it dissolve and release carbon dioxide gas when dropped in water. In this experiment, my lab partner, Rebecca, and I are trying to find a way to make Alka Seltzer dissolve faster in water. Rebecca and I both decide that if we increase the temperature of the water or make the water hotter, then the Alka Seltzer will dissolve faster because I know when salt and sugar dissolve in hot water, they dissolve faster. I predict that this same result would apply to this experiment.

8.When the reaction is completed, record the volume of gas in the graduated cylinder. Record observations about which reactant was the limiting reactant.

The volume of carbon dioxide gas produced from a reaction was measured in order to determine what carbonate sample was used. A gas assembly apparatus was used to capture the gas from a reaction between an unknown carbonate and 6M hydrochloric acid; three trials were performed. The mass of the unknown carbonate was determined, and the reaction occurred in a test tube. The volume of gas produced by the reaction was measured, and the partial pressure of carbon dioxide was calculated after the partial pressure of water vapor was determined using Dalton’s Law of Partial Pressures. The percent mass of carbon dioxide gas was then calculated, and the average mass percent was compared to the table of known carbonates. It was concluded that the unknown carbonate sample used in the reaction was magnesium carbonate.

The soda ash form experiment 3 was obtained. A 250 ml beaker was obtained and rinsed.

1. In this experiment, you will study the relationship between temperature of a gas sample and the pressure it exerts. Using the apparatus shown in Figure 2, you will place an Erlenmeyer flask containing an air sample in a water bath and you will vary the temperature of the water bath. Connect the Temperature Probe to Channel 2 of LabQuest. Choose New from the File menu.

8. Repeat steps 4. to 7. to continue collecting the gas produced by the reaction between calcium carbonate and hydrochloric acid, until 45mL of gas is filled in the gas syringe, as indicated by to what number on the gas syringe the plunger has been pushed outward.

The ideal gas law relates the four conditions that are used to describe a gas, which are pressure, volume, number of moles, and temperature, along with the gas constant, R. This law is represented in an equation, which equates pressure multiplied by volume with the number of moles times the gas constant and the temperature. It is represented in the equation, PV = nRT. “R” represents the gas constant, which replaces the need for a second sample of gas when solving for a variable. The value of the gas constant depends on its units, kPa or atm, which can either be 8.31 or .0821, respectively. With this formula, anything can be solved for, which makes finding any of the variables far easier. This includes the number of moles. When the mass collected of a substance is divided by the moles of that same substance, it equates the molar mass in grams per mol of that, which would prove to be very useful in this lab.