In this lab, lab 4.3 Comparing the Concentrations of Saturated Solutions, we set out to find and compare the solubilities of two solids in water. In addition, we tested if solubility is a characteristic property of a solid in a given liquid. This lab allowed us to test and use a reliable way to measure the solubility of a solid. This lab can be replicated for any solid with the same procedure, thus it gives us a method to calculate solubility. The two solids we tested in this experiment were NaCl (Sodium Chloride) and NaNO3 (Sodium Nitrate).
To begin the experiment, we measured 5cc of water and 5g of NaCl and added them to a test tube. Next, we stoppered the test tube and shook vigorously for two or three minutes. After we observed that the solution was saturated and massed an evaporating dish (18.89g) and poured most of the solution into it, while being careful not to pour any undissolved solid into the dish. Next, we massed the evaporating dish with the solution and found it to be 23.32g. The next step was to slowly evaporate the solution in the evaporating dish using a hot plate. Once the liquid was evaporated from the solution, to the best of our ability, we massed the remaining solid in the dish, which we found to be 20.32g. This was the last step of the physical portion of the experiment, and we proceeded to the calculations. First, we found the mass of the remaining solid by subtracting the mass of the evaporating dish from the mass of the solid and evaporating dish, which we found to be 1.43g. To find the mass of the evaporated water we subtracted the mass of the solid and evaporating dish from the mass of the solution and evaporating dish, which we found to be 3g. Because the density of water is 1g/1cc, the mass is the ...
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..., the dissolved substance, in a given solvent, the dissolving substance. Solubility is a characteristic property of a given solid in any given liquid, and when the solubility of a solid is reached the solution is considered saturated. A saturated solution is a solution in which the maximum amount of solute has been dissolved in the solvent and no more solute can dissolve. Furthermore, in lab 4.1 we incrementally added solid until the solution was saturated and noted when it was saturated but did not find the solubility of the solid. Contrary to lab 4.1, in lab 4.3 we started with a saturated solution, and then removed the water, giving us the maximum amount of solid per volume of liquid otherwise known as the solubility of the solid. In conclusion, lab 4.3 allowed us to find the accurate solubility of two solids and gave us a method to find the solubility of a solid.
Solubility test was used to determine if unknown white compound was soluble in water. To conduct the solubility test, many materials were used such as flask, glass rod, scale, and chemical used was unknown white compound. First, 0.25 gram of unknown white compound carefully measured on scale. Then, the 0.25 gram of unknown white compound added to 100 mL of water and dissolved it using the glass rod. While the unknown
For this solution, 5 mL of the solution with 2.5 mL of AMV was placed in the cuvette. The cuvette was placed inside of spectrophotometer and the amount of absorbance was recorded. This procedure that involves a solution with a known concentration was repeated for the concentrations:1.0x10-4 M,5.0x10-5 M,2.0x10-5M, and1.0x10-5M.A unknown solution absorbance was measured by putting 5 mL of unknown solution with 2.5 mL AMV in a cuvette. The cuvette was placed in the spectrophotometer and the amount of absorbance was recorded. The procedure that deals with the unknown solution was repeated 2 more times with the same solution and the same amount of solution and AMV.
A precipitation reaction can occur when two ionic compounds react and produce an insoluble solid. A precipitate is the result of this reaction. This experiment demonstrates how different compounds, react with each other; specifically relating to the solubility of the compounds involved. The independent variable, will be the changing of the various chemical solutions that were mixed in order to produce different results. Conversely the dependent variable will be the result of the independent variable, these include the precipitates formed, and the changes that can be observed after the experiment has been conducted. The controlled variable will be the measurement of ten droplets per test tube.
In addition, the water is mixed with salt, which allows the cold pack to stay cool. The mixture that occurs between the salt and the water causes an endothermic reaction, which means that heat is absorbed. Due to the heat absorption, the temperature of the solution will decrease substantially. The cold pack experiment lab allowed us, the students, to apply theories learned in class to actual real life experiments; such experiments prepare us for future tasks the will be put forth to determine. Our main trajectory through this assignment was to determine what our unknown salt was, through experimental analysis.
Prediction: Draw a sketch to show the shape of the curve you expect for the solubility of a typical solid dissolving in water at different temperatures. Plot solubility on the y-axis and temperature on the x-axis.
The first step that we took to accomplish our goal was to put on our safety goggles and choose a lab station to work at. We received one 400ml beaker, one polyethylene pipet, two test tubes with hole rubber stoppers, two small pieces of magnesium (Mg), one thermometer and a vial of hydrochloric acid (HCl). We took the 400ml beaker and filled it about 2/3 full of water (H20) that was 18 OC. Then we measured our pieces of Mg at 1.5 cm and determined that their mass was 1.36*10-2 g. We filled the pipet 2/3 full of HCl and poured it into one of the test tubes. Then, we covered the HCl with just enough H2O so that no H2O would be displaced when the stopper was inserted. After inserting the stopper, we placed the Mg strip into the hole, inverted the test tube and placed it in the 400ml beaker. HCl is heavier than H2O, so it floated from the tube, into the bottom of the beaker, reacting with the Mg along the way to produce hydrogen gas (H2). We then measured the volume of the H2, cleaned up our equipment and performed the experiment a second time.
Background: The density of water is 1 g/mL. In order to find density, you must do mass divided by volume. You find solid volume by multiplying the length by width by height or by using displacement. You find mass by weighing the substance. In previous experiments, it is seen that alcohol dissolves faster than water.
Solid A was identified to be sodium chloride, solid B was identified to be sucrose, and Solid C was identified to be corn starch. Within the Information Chart – Mystery White Solid Lab there are results that distinguishes itself from the other 4 experimental results within each test. Such as: the high conductivity and high melting point of sodium chloride, and the iodine reaction of corn starch. Solid A is an ionic compound due to its high melting point and high electrical conductivity (7), within the Information Chart – Mystery White Solid Lab there is only one ionic compound which is sodium chloride, with the test results of Solid A, it can be concluded that is a sodium chloride. Solid B was identified as sucrose due to its low electrical
The mixture was poured through a weight filter paper and Sucrose washed with a 5ml of dichloromethane. The resulting solid was left in a breaker to dry for one week, to be measured. Left it in the drawer to dry out for a week and weighted it to find the sucrose amount recovered amount.
The same procedure was done using 10ml of CV and 20ml of sodium hydroxide, both separately diluted to 50ml and added in a large beaker. The absorbance was recorded. In the last trial, 10ml of CV, 10ml of NaOH were diluted to 50ml. Before adding the two mixtures, 1ml of soap was added to the NaOH solution and then poured into a large beaker, along with the CV. Absorbance was recorded and the materials
11.) Subtract the mass of the evaporating dish from the mass of the evaporating dish and it's contents. Multiply that number by 10 to get the solubilty in grams per 100 cm3 of water.
When preformed each of these experiments with each temperature of water, plugging them into the equation (Delta)(Ti – hot – Tf) T Hot x Cp x Mass(Cold) = (Delta)(Tf – Ti – Cold) T Cold x Cp x Mass(Hot)(d
In a 100ml beaker 30mls of water was placed the temperature of the water was recorded. 1 teaspoon of Ammonium Nitrate was added to the water and stirred until dissolved. The temperature was then recorded again. This was to see the difference between the initial temperature and the final temperature.
According to the conductometric titration, the concentration of Ba(OH)2 (aq) was 0.196 M. Calculations based on gravimetric analysis revealed a concentration of 0.0669 M. Evidently, there is a high degree of imprecision between the values determined by each technique. It appears however that the gravimetric analysis was more accurate. The standard deviation for BaSO4 mass was 0.035 and the confidence interval was ±0.0256 g. This illustrates that there is 90% certainty that the actual mass of the BaSO4 precipitate was within 0.0256 g of the calculated mean (0.156 g). It should be noted that an outlier (1.45 g precipitate) was removed from the gravimetric analysis calculations due to being 9.29 times greater than the average. The standard deviation for end point volume – the basis of calculations for the conductometric titration – was 6.616. The confidence interval was ±5.443 mL. The much larger confidence interval for end point volume illustrates a higher degree of uncertainty regarding the precision of this measurement. For this reason, it appears that gravimetric analyses are more suitable for determining saturated solution concentration. This has importance in research where the solubility product (Ksp) needs to be determined or when predictions need to made regarding whether a precipitate will form. One of the principle reasons why conductometric titration
First, the mass of the beaker being used was recorded, then about 1g of baking soda was added and the mass recorded. Next, the mass of just the baking soda was found and recorded. Then, the contents were boiled until dry then weighed and mass recorded after cooling off. Finally, the mass of jus the salt, or sodium chloride, was found and recorded.