Dispose of the NaCl, rinse and dry the glassware. Weigh the empty glassware and record.…
After the calcium carbonate was filtered through, the mass was 2.13g, so the calcium carbonate weighed .36g. The stoichiometry that we performed said that the predicted mass of calcium carbonate was .51g, so the percent yield is 71%. For trial two, the mass of the empty filter was 1.84g. Along with the calcium carbonate, the filter weighed 2.00g, which tells us that there is .16g of calcium carbonate, and our predictions state that we should have ended up .34g, having a percent yield of 47%. Trial three, the filter weighed at 1.82g and after the filtration it weighed 2.15g. We scaled out .33g of calcium carbonate as compared to our predicted stoichiometry, .40g, which the yield resulted at 83%. The combinations of reactants that produced the most product were .75g of calcium chloride and sodium carbonate, according to the stoichiometry, that was what i predicted. None of these trials show that our experimental mass was the same as our predicted mass. Each trial that was performed had a percent yield not even above 100%, which leads for me to believe we definitely made a mistake during our procedure, such as writing down wrong information or not calibrating out the balance/scale. Those seem to be the only explanation for why the ratios were…
In this experiment we are going to get a better understanding of chemical stoichiometry. We are going to be reacting sodium bicarbonate (NaHCO3) and sodium carbonate (Na2CO3) with hydrochloric acid (HCl). To start off the mass of two unknown substances (being the sodium bicarbonate and sodium carbonate) will be taken. We will need to construct balanced equations for both of the reactants with the HCl and use this to guide us to figure out how much HCl will be needed to react with each of the unknown substances. When this part is through we will then need to find the percent yield (actual yield/theoretical yield x 100). Determining the mass of sodium chloride at the end of the experiment is the actual yield. To find the theoretical yield we will need to heat the sodium chloride so that all the CO2 evaporates and that will leave us with the theoretical yield of sodium chloride.…
Through the conservation of mass, the mass of carbon dioxide can be found. The ‘law of conservation of mass’ states that mass cannot be created or destroyed in chemical reaction. Therefore, when sodium carbonate and hydrochloric acid reacted together, there was no mass created or destroyed. The law also explains that, “when a chemical reaction rearranges atoms into a new product, the mass of the reactants is the same as the mass of the…
The purpose of the particular is to study the nature of ionic reactions and to learn how to write balanced equations and to learn how to write net ionic equations for precipitation reactions.…
If an air bag has a volume of 36 L and is to be filled with nitrogen gas at a pressure of 1.15 atm at a temperature of 26.0°C, how many grams of NaN3 must be decomposed?…
Experiment and Observations: As I performed the lab, I had to retrieve all my equipment’s from my labpaq. As I started to setup, I had to weigh out 1.0 gram of CaCl2*2H2O on the digital scale. After it was weighed, it was added to the 100 mL beaker and 25 mL of distilled was added and stirred. Next, I had to figure out the amount of the second reactant, so that it can be added to the solution. I had to perform stoichiometry to figure out the amount of Na2CO3 is needed to make a precipitate of calcium carbonate. After the calculations, I arrived at .72 grams of Na2CO3 and rounded to the nearest tenth to mix with 25 mL of distilled water. After both of the reactants were mixed separately with distilled water, they both were clear color. As soon as you added the solution of Na2CO3 to CaCl2*2H2O the color of solution changed to a cloud white color. When both solutions are mixed, the paper filter that was provided with the lab must be weighed and recorded. Then you pour the solution into the paper filter to filter out the precipitate and dry the filter to weigh the mass of the precipitate when it dries. After it dried, it was weighed and stoichiometry was performed to see what the…
The data gathered and calculated in the experiment accurately portrayed the way the reactions would have taken place. The chloride analysis was a little bit off from other groups due to the fact that our AgCl was in clumps, creating less surface area, thus our product took longer to burn and may not have burned correctly compared to other groups; yet there are several experimental factors that could have caused us to have different results than other groups, i.e. different measurements for samples. Our sources of error could have included eye measurement error, timing of set solutions error, measurement errors, and small calculation errors. Among other variables, the calibration of the analytical balance and spectrophotometer could have been off slightly, yet our results, like most other groups, still followed the general trend line generated by the graph using Beer’s Law. The measurement errors could have occurred due to the fact that one partner’s perspective of a measurement could be different than the others, but the lab cannot be preformed solo. When it comes to improving the lab, there aren’t to many ways to ensure accurate measurements due to the fact that in any experiment there are human and environment variables that cannot be accounted for, or even prepared for. In any experiment there will always be human error.…
Purpose: To determine which mole ratio of Zinc and Copper II Sulfate produces the greatest temperature change in degrees celsius.…
When we bake/cook something, we use a specific amount of each ingredient. Imagine if you made a batch of cookies and used way too many eggs, or not enough sugar. YUCK! In chemistry, reactions proceed with very specific recipes. The study of these recipes is stoichiometry. When the reactants are present in the correct amounts, the reaction will produce products. What happens if there are more or less of some of the reactants present?…
100 mL of water is already in the calorimeter. Use the density of water at 25°C (0.998 g/mL) to…
Describe the patterns and trends that you see. Are there any relationships between physical state and the property you chose? [10 pts]…
The analysis for experiment four: Stoi 903was conducted by Me (name) and my partner (name). They analysis performed for experiment four: Stoi 903 took place at Texas State University- San Marcos in room 117 of the chemistry building. The concentrations used in the experiment were both .5 M sodium hypochlorite and sodium thiosulfate. The concentrations of the solutions found in the dumpster were calculated to be .806 M (both sodium hypochlorite and sodium thiosulfate as well). This was found by taking the 6.0% (by mass) sodium hypochlorite and multiplying it by 1 gram of solution, 1000 mL and 1 mol NaClO. This result was then divided by the result of 100g of solvent, multiplied by 1 mL of solution and 1L which equals 60g NaClO. 60g was then divided by the molar mass of NaClO (74.44) which equals .806 mol NaClO. The same can be done for sodium thiosulfate which results in the same molarity.…
We know that that the end point of the titration is reached when, after drop after careful drop of NaOH, the solution in the flask retains its pale pink color while swirling for about 30 seconds (as opposed to the pink color simply disappearing as the base mixes into the solution).…
1. In the chemical formula for ammonia, NH3, what does the subscript 3 represent? (a) the number of ammonia molecules that will bond together (b) the number of nitrogen atoms in each molecule of ammonia (c) the number of nitrogen and hydrogen atoms in each molecule of ammonia (d) The number of hydrogen atoms in each molecule of ammonia 2. The diagram above shows a block from the periodic table. The number six represents the following consumers eats only producers?…