Stoichiometry Lab Report

The experiment confirmed that our hypothesis was correct, the hotter the water is, the faster an Alka-Seltzer tablet dissolves faster. We expected the hotter water to dissolve the tablet faster because the particles move faster, thus making the tablet dissolve faster as well.

Then with a pipet, place slowly with hydrochloric acid, 10 ml, into the sodium hydrogen carbonate until the bubbles stop. Then with the product, heat until it seems as if all the water in the dish is evaporated. Originally the product was supposed to be 2.09g of hydrochloric acid, however there was a miscalculation of the mass of the sodium hydrogen carbonate, and that mass turned out to be 3.07g. The final mass for the product was supposed to be 2.14g as a mass of the product. After all the procedures were completed, the mass that was received from the lab calculations was 2.45g. This was a 114.55 percent error to the lab. The large error could have lead to many different things. One of the things that the error could have been caused was miss calculating the mass. While measuring the sodium hydrogen carbonate, the mass of the evaporating dish mass, 46.50g, had altered when it was zeroed and put the 3.00g of the sodium hydrogen carbonate. Then it was massed again together and it was 49.57g. Another possible way that the mass was altered the way it was, it that all the water wasn’t evaporated. There was also a little splatter outside the dish. That helped lessening the mass that was already too big. Finally an important error that happened was not letting the evaporating dish cool after it was heated. Those are some ways that the lab error could

The purpose of this experiment was to see how the amount of baking soda dissolved in vinegar would affect the pH of the vinegar. We conducted the experiment by testing different amounts of baking soda in constant amounts of vinegar, and dropping the solutions on pH paper. By comparing the colors on the pH paper to a list of colors in relation to numbers on the pH scale, we were able to find out that as more baking soda is added, the pH of the solution goes up as well.

Another error that occurred while doing this experiment is when the Alka-Seltzer tablets were broken into smaller pieces. Small pieces of the Alka-Seltzer tablets could be seen on the table after finishing the experiment, which meant that some had been lost causing an inaccurate result. A solution to this problem is by placing the Alka-Seltzer tablet into a bag and then break it into smaller pieces. The Alka-Seltzer tables can then be poured into the balloon.

Additionally, if tap water were used in place of distilled water to dissolve the dried alkali metal carbonate, there would be an increase in the apparent molar mass. Tap water has other ions in it which would have reacted partially with the alkali metal carbonate, making it seems as though there was less alkali metal carbonate than there actually was. Again, this would decrease the moles of alkali metal carbonate and thus increase the molar mass (4). One precaution taken to get the most accurate measurements possible was heating the calcium carbonate for 15 minutes,

The distilled used in this experiment was slightly acidic with a pH of 5.27 when water should have been around a pH of 7. This could have been because carbon dioxide in the air may have been absorbed into the distilled water.

The first experiment the students choose was putting the baking soda and vinegar into their palms. Lots of students said, that they could feel a frozen and bubbly sensation where they had put the baking soda and vinegar. Many said it felt like drinking ice cold carbonated drinks but, the carbonation feeling was on their hand. After that, many choose to do the table experiment. I asked Morgan Michelle Steele, one of Mrs. Barrett’s many students, what she had experienced during the experiment. When she set the vinegar on top of the baking soda, she told me that “the aftermath of the mixing of the products was that it created lots of bubbles, fizzing, and steam coming off the top of the pile. It was a mini explosion of carbonation on the table!” She added. The last experiment the students did was putting the mixture into the beaker. For many students it produced lots of bubbles, fizzing, and it even had aggrandized so much that liquid had overflowed out of the beaker. Unfortunately, not all students worked fast enough to complete the third test, so they had to clean up and start the class

As the amount of the reaction’s product of oxygen and water (figure 3) was observed by reacting with detergent and measuring the amount of froth produced, the volume of froth indicated the rate of reaction between catalase and hydrogen peroxide. However, the raw data of the first average bubble production, 40ml at 6°C, is constantly discordant with the introduction’s knowledge on the effects of temperature on particle collision, therefore is indicative to have been an outlier, affected by errors, and hence is excluded from the line of best fit. Discounting the outlier, the trend in figure 4 highlighted by the line of best fit supports the hypothesis and can be explained by the knowledge discussed in the introduction. Figure 4, supporting the

My partner Alyssa Roeung and I will be demonstrating the rapid inflation of airbags through our experiment. The basic materials we will be using are sodium bicarbonate (baking soda), acetic acid (vinegar), a measuring cup, and a Ziploc bag. We will be combining both reactants within the Ziploc bag to create a gaseous product to show how an airbag would inflate during an impact. The chemical equation for acetic acid is CH3COOH and it is an aqueous solution. The chemical equation for sodium bicarbonate is NaHCO3 and it is a solid. When both reactants combine they produce carbon dioxide, water, and sodium acetate. NaHCO3 (s) + CH3OOH (aq) → CO2H2ONaCH3COO.

Results and Discussion: The first process of the experiment was when 1.0545 grams of the pieces of aluminum cans were mixed with potassium hydroxide to form the products potassium aluminum sulfate and water. The equation shown below is the unbalanced version Al(s)+KOH(aq)+H2O(l)KAl(OH)4(aq)+H2(g) .The new balanced equation was 2Al(s)+2KOH(aq)+6H2O(l)2KAl(OH)4(aq)+3H2(g). The reaction shown above is a redox reaction due to the transfer of electrons from one element to another.The aluminum was oxidized from 0 to 3+ and the hydrogen in potassium hydroxide was reduced from 1+ to 0. As the reaction was being completed a gas was formed as well as a color change in the liquids used. In order to speed up the reaction a hot plate was used. All of this was done under a fume hood to make sure none of the gases formed was in the air. The next chemical process in the experiment was when the 20 mL of sulfuric acid was added to the solution. The balanced equation is 2KAl(OH)4(aq)+H2SO4(aq)2Al(OH)3(s)+K2SO4(aq)+2H2O(l) but the total ionic equation is what was used which was Al(OH)4-(aq)+H+(aq)Al(OH)3(s)+H2O(l). The reaction shown was an acid-base

Two sodas containing citric acid were investigated in this experiment. Each soda was titrated using one of the two experimental methods. These methods are the traditional titration and the modern titration. Carbonic acid was already removed from the soda by boiling it.

In this ADI Lab, the overall question was ¨Stoichiometry and Chemical Reactions: Which balanced chemical equation best represents the thermal decomposition of sodium bicarbonate?¨. To better understand this question, here are definitions of key words of the overall question. Stoichiometry is the science of the relationship between the relative quantities of substances taking part in a reaction or forming a compound. A balanced chemical equation is an equation of a chemical reaction where the number of atoms for each element in the reaction and the total charge is the same on both sides of the equation. Finally, thermal decomposition is the a chemical reaction where heat is used to break down a substance. The particular testable question that was given was ¨Which balanced chemical equation best represents the thermal decomposition of sodium bicarbonate?¨. The four given equations were NaHCO₃(solid)→NaOH(solid)+CO₂(gas), 2NaHCO₃(solid)-->Na₂CO₃(solid)+CO₂(gas)+H₂O(gas),

Any shift in the equilibrium would be reverted back after the second solution would be added since the acid would just neutralize the base (and the base neutralize the acid.) When 1 M HCl was added to the 1 mL of 0.1 M K2CrO4, it caused the originally clear yellow solution into a yellow orange color. When 1 M NaOH was then added after, the solution returned to its original color which was clear yellow. The reverse occurred when 1 M NaOH was added to the 1 mL of 0.1 M K2Cr2O7 then 1 M HCl. When added with 1 M NaOH first, the originally clear orange solution became yellow orange then back to orange again when 1 M HCl was added. This shows that what ever acid or base was added, the counterpart was able to neutralize the added solution and revert the reaction.

The purpose of this experiment was to use stoichiometry to calculate the volume and percent yield of CO₂ produced from a reaction of acetic acid (vinegar) with baking soda.

Crude sodium bicarbonate or commonly known as soda ash may contain amounts of impurities like chlorides and hydroxides. The total acid neutralizing capacity of a soda ash sample, its alkalinity value, was stated in terms of mass of sodium carbonate. In doing so, any sodium hydrogen carbonate present in the sample was converted to its equivalent neutralizing capacity in terms of sodium carbonate. A mass of the impure sample was dissolved and diluted in distilled water. 3 drops of indicator was mixed and the solution