Mukund Balaji, Jacob Jiang, Carolyn Zheng Honor Chemistry Mrs. Marino May 1, 2023 Thermal Decomposition of Sodium Bicarbonate Introduction: In this experiment, heat is added to a compound known as sodium bicarbonate, or in a chemical sense, NaHCO3. This compound is also known as baking soda in a domestic setting and has several uses due to its chemical nature. This lab tests the thermal decomposition of this compound by heating this compound under a Bunsen burner. There are four possible equations that will theoretically be used. These equations are as follows: NaHCO3 (s) → NaOH (s) + CO2 (g) 2NaHCO3 (s) → Na2CO3 (s) + CO2 (g) + H2O (g) 2NaHCO3 → Na2O (s) + 2CO2 (s) + H2O (s) NaHCO3 → NaH (s) + CO (g) + O2 (g) This lab will determine the correct …show more content…
Light the Bunsen burner. Heat the crucible for two minutes and then turn off the Bunsen burner. Wait for the crucible to cool to room temperature. Measure and record the mass of the crucible Keep the crucible on the mass balance and tare the mass balance. Pour about 2.00g of sodium bicarbonate (NaHCO3) into the crucible. Measure and record the actual mass of the sodium bicarbonate. Place the crucible with sodium bicarbonate onto a ring clamp above the bunsen burner. Light the Bunsen burner. Heat the crucible for 15 minutes and record any observations. Wait for the crucible to cool to room temperature. Measure and record the mass of the crucible and its contents. Place the crucible back on the ring clamp. Heat the crucible again for 2 minutes. Rerecord the mass of the crucible and its contents. Repeat steps 14-16 until the difference between the existing and new measurements is lesser than 0.02 grams. …show more content…
To begin with, the fact that the mass was reduced shows that there is some sort of reaction that did take place. In all cases of reactions, the law of conservation of mass states that mass cannot be created or destroyed. With this in mind, it can be concluded that the mass that was “lost” was transferred into a different substance, which in this case was carbon dioxide and water vapor. These substances, as they are in their gaseous state, do not remain in the crucible, and escape into the surrounding area. This situation causes a reduction in the mass of the sodium
the triple beam balance scale to measure the mass of the cup and the jar 3.Mix sugar and water in a beaker 4.Place the mixed solution onto a hotplate 5.Stir the solution 6.After stirring measure the temperature of the solution 7.Create a cross with
After we put the substance on the burner, we weighed it. Each time after we put it on the burner came with the exact same number: 21.16 grams. After we found the mass of the crucible, cover, and hydrated sample, and the mass of the crucible, cover, and dehydrated sample, we subtracted the two values to get the mass of water evolved: 0.24 grams. Then, we subtracted that value to the mass of the hydrated sample to get the mass of the dehydrated sample: 0.76 grams.
Put the beaker with the water and the metal on the wire gauze of the ring stand that has the bunsen burner under it. Fill the graduated cylinder with enough water to about fill the calorimeter and record the amount of water and the temperature of the water that is in the graduated cylinder. When the water starts to boil in the beaker, use the thermometer to record the temperature of the water. Pour the water from the graduated cylinder into the calorimeter. Use the crucible tongs to take the metal out of the beaker and place the metal into the calorimeter and close the
Next, fill the graduated cylinder with water, then put a hand over it and flip into the pneumatic trough. While doing this step make sure the least bubbles get in. This can affect the results of the experiment. Stick the tubing into the cylinder and put the sodium bicarbonate into the side arm erlenmeyer flask. Put the other end of the tubing on the erlenmeyer flask.
Monitor the reaction and when when the reaction is near completion let some smoke escape by tilting the lid of the crucible When the reaction ceases, turn off the Bunsen burner and let the crucible cool completely before handling it. Weigh the crucible and record the weight Using a pipette, add a small volume of water to the solids in the crucible Stir the mixture with a glass rod until the mixture forms a paste Return the crucible to the Bunsen burner and heat it for several minutes until all the water has evaporated and the solids have turned light grey → indicating conversion to magnesium oxide. Turn off the Bunsen burner and let the crucible cool completely Weigh the crucible with the lid and record the weight Subtract the initial weight of the crucible and lid from the final weight of the crucible, lid, and magnesium oxide to obtain the mass of magnesium that reacted with oxygen. → this information will be used to calculate the empirical formula for magnesium oxide and prove it. Clean the crucible thoroughly to ensure it's ready for the next use.
Measure enough water in grams to cover the block in a beaker. Measure the temperature of water in (℃). Put water in beaker with the block and place over a lighted bunsen burner.
The evaporating dish was placed on top of the wire gauze and covered with the watch glass. The Bunsen burner was used to heat the water to a boil until the water had evaporated, leaving a dry, white solid (salt). The evaporating dish with the watch glass containing the salt residue was then weighed and recorded to 0.001 g. The mass of the evaporating dish and watch glass containing the salt residue was subtracted from the mass of just the evaporating dish and watch glass which gave the mass of the
Measure out 0.035 - 0.045g of magnesium ribbon and tie a string to it and record the mass of the ribbon. Pour 6 mL of HCl into the eudiometer. Carefully pour 50-60 mL of distilled water to fill up the rest of the eudiometer.
Modifications of this procedure include the use of hot plates instead of Bunsen burners, and heating t-butyl alcohol to 60-65 ℃ instead of 50 ℃. Other modifications include the use of weighing boats to measure an amount of unknown instead of weighing paper, and completing one run of unknown 2 instead of two runs of unknown 2. Summary of
Materials and Equipment Iron ring and ring stand Crucible and pipe stem triangle Bunsen burner and striker Sodium hydrogen carbonate (baking soda) Scoopula Heat safe gloves Goggles Electronic scale Safety Notes Wear lab goggles in the lab Do not touch crucible without heat safe gloves Allow crucible to cool completely before cleaning out Procedure Mass the crucible. Zero the balance while the crucible is on it and mass 3.00g of baking soda. Place the crucible with baking soda on top of a pipe stem triangle on the ring stand.
The scientist recorded the mass of the Sodium Hydroxide in the data table. After the mass gets recorded, the scientist takes the graduated cylinder off the scale, while the Sodium Hydroxide remains in the graduated cylinder. Next, the scientist took the beaker and the test tube and placed the two materials on the digital scale. The scientist pressed the zero on the digital scale to zero out the scale. While the materials stay on the scale, The scientist took the pipette and filled the pipette up with Copper Nitrate.
To do this you first have to place the weighing boat on the scale and hit tare, so it reads zero and then place copper(II) sulfate pentahydrate on the weighing boat. Transfer the copper(II) sulfate into a 250-mL beaker. Rinse the weighing boat with 5 mL of purified water in small quantities to rinse off leftover chemical into the beaker. Spin the beaker gently to dissolve the solid. Rinse the sides of the beaker with small amounts of the 5 mL of purified water.
i. Grind the powder in the mortar and pestle. At this stage weigh 1.6 g powder, and mold it into a pellet (3 mm thick, 12 mm in
Fit this gooch crucible on a filtration flask and connect filtration flask to vacuum pump. Take 25 ml sample and diluted
The trend between these two variables, clearly seen in Figure 1, is that a rise in the increase of the concentration of vinegar (in %) directly increased the volume of Co2 bubbles produced (ml ). So, every 20% increase in the concentration of vinegar caused a direct rise in the volume of carbon dioxide bubbles produced. These results can be explained by the Law of Conservation of Mass ( discovered by the scientist Antoine Lavoisier), which states that matter in any form of reaction ( chemical or physical) cannot be created or destroyed. It also states that the mass of products in a reaction must also equal the mass of the reactants in it. So, according to the Law of Conservation of Mass, the mass of the sodium bicarbonate and vinegar must also equal the mass of carbon dioxide and other by-products produced.