Purpose: Collect the experimental data necessary to construct a solubility curve for potassium nitrate (KNO3) in water. Materials: Balance, hot plate, microspatula, 4 boiling tubes (18 x 150-mm), boiling tube holder, boiling tube rack, 400-mL beaker, thermometer, graduated cylinder, stirring rod, iron ring, utility clamp, wire gauze, marking pencil, potassium nitrate (KNO3), distilled water, safety goggles, lab apron Procedure: 1. Using a marking pencil, the boiling tubes were labeled 1 through 4. They were placed on the boiling tube rack. 2. On a balance, exactly 2.0 g of potassium nitrate (KNO3) were measured out. The salt was poured into boiling tube #1. 3. Step 2 was repeated for the following masses of KNO3 and added to the boiling …show more content…
Exactly 5.0-mL of distilled water was added to each boiling tube. 5. A 400-mL beaker was filled about three-fourths full with tap water. This was used a water bath. The beaker was placed on a hot plate and heated to 90C and the temperature was adjusted to maintain the water at about this temperature. 6. The KNO3-water mixture was stirred with a glass stirring rod until the KNO3 was completely dissolved. The stirrer was removed and rinsed. Using the boiling tube holder, the tube was removed. 7. Step 6 was repeated with boiling tube #2 and a warm thermometer (after being placed in the hot water bath) was placed into the solution in boiling tube #1. The boiling tube was held up to the light and the first sign of crystallization was observed As the instant crystallization began, the temperature was observed and …show more content…
2.0g/5.0-mL x 20 = 40.g/100-mL 4.0g/5.0-mL x 20 = 80.g/100-mL 6.0g/5.0-mL x 20 = 120g/100-mL 8.0g/5.0-mL x 20 = 160g/100-mL 2. See graph paper for 2 and 3. Conclusions and Questions: 1. A. 30C: 30g KNO3 B. 60C: 105g KNO3 C. 70C: 130g KNO3 2. Saturated is a term describing a mixture that already contains the maximum amount of solute that will dissolve at that temperature. When a solution can hold more solute than it currently contains, it is called unsaturated. When a solution contains even more that solute than will dissolve, it is supersaturated. 3. A. Supersaturated because that point falls about the solubility curve for KNO3. B. Unsaturated because that point falls below the solubility curve for KNO3. 4. No, not all ionic compounds fit that description, however the solubility of most ionic compounds increase along with the temperature. When a substance dissolves, it goes from a solid to a liquid, which is an endothermic reaction. When heat is added and the temperature become higher, the extra heat favors the endothermic reaction causing more solid to dissolve rather than crystallize. 5. The solubility of a gas decreases with temperature (e.g., cold water will hold more gas than hot water). For sketch, see back of graph
Firstly, when testing temperatures at 30°C and 40°C, the water was. sometimes heated more than needed, so I had to wait until it cooled. down to the required temperature. To avoid this happening, a. thermostatic water bath could have been used, because I could set it. to the required temperature.
The procedure of the lab on day one was to get a ring stand and clamp, then put the substance in the test tube. Then put the test tube in the clamp and then get a Bunsen burner. After that put the Bunsen burner underneath the test tube to heat it. The procedure of the lab for day two was almost exactly the same, except the substances that were used were different. The
3. Using a graduated cylinder, measure and pour 5 ml of the CaCl solution into a test tube and use a utility clamp to fasten the test tube to
Plan 1. Collect 4 different sized beakers 2. Boil some water in the kettle 3. Pour 50ml into each beaker 4. After 1 minute check temperature 5.
Potassium is an element on the periodic table that is symbolized by the letter K. The atomic number of this element is 19. At room temperature this element is a solid. Potassium can be found in two forms: either pure or compounds. Pure potassium is described as a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive in water However, Potassium forms many compounds such as Potassium chloride, which is the most common potassium compound (Gagnon, 1). This form of Potassium is especially used in fertilizers as a salt substitute. Another potassium compound is Potassium hydroxide, which is used to make soap, detergents and drain cleaners. Potassium carbonate is used to make some types of glass and soaps. This is also obtained as a byproduct of ammonia. Lastly, Potassium superoxide can create oxygen from water vapor and carbon dioxide. An example of this reaction is “2KO2 + H2O + 2CO2 => 2KHCO3 + O2” (Gagnon, 1). Gagnon also says, “it is used in respiratory equipment and is produced by burning potassium metal in dry air. Potassium nitrate (KNO3), also known as saltpeter or nitre, is used in fertilizers, match heads and pyrotechnics” (Gagnon, 1). Sir Humphrey Davy discovered this element in England in 1807 (Helmenstine, 1). Steve Gagnon, maintainer of the Jefferson Lab website page says, “Sir Humphry Davy first isolated metallic potassium in 1807 through the electrolysis of molten caustic potash (KOH)” (Gagnon, 1). Gagnon also writes, “a few months after discovering potassium, Davy used the same method to isolate sodium. Potassium can be obtained from the minerals sylvite (KCl), carnallite (KCl·MgCl2·6H2O), langbeinite (K2Mg2(SO4)3) and polyhalite (K2Ca2Mg(SO4)4·2H2O). These minerals are often found in ancient...
Rinse your beaker thoroughly to wash any excess powder. 12. Repeat steps 7-11 3 more times for reliability. To make sure the temperature still stays hot by continue heating the water a little bit using the hot plate. 13.
Measuring cylinder to measure small amounts of fluids. Pipette to gather small amounts of fluids. Test tube holder to hold test tubes. 2. Molar Salt solutions to submerge potato chips in.
5.) One at a time, place your test tubes in the water bath and heat the first test tube to 25 , the second to 50 , the third to 75, and the last to 100 degrees c. Remeber to stir with your stirring rod every so often.
In a 100ml beaker place 50mls of water, measure the temperature of the water and record this initial temperature onto a table. Set the timer and add one teaspoon of Ammonium Nitrate to the water, stir this continuously until the Ammonium Nitrate has dissolved.
Mixed melting point was used to confirm the identity of the product. The smaller the range, the more pure the substance. When the two substances are mixed; the melting point should be the same melting range as the as the melting range obtained after filtering. If the mixed melting point is lower one taken from the crystals, then the two substances are different.
3. Why are the crucible and lid heated at the beginning of the experiment before being weighed?
2. In the large beaker, put water and boil it completely. After that, remove the beaker from heat. 3. Sample tubes (A-D) should be labeled and capped tightly.
In order for KNO3 to be dissolved, it must come into contact with
tube. Add 6 mL of 0.1M HCl to the first test tube, then 0.1M KMnO4 and
In this experiment the Sodium Hydroxide solution went through three different phases where its quality and quantity changed. The first phase was called I. Preparing Approximately 0.1M NaOH, 1000mL of clear distilled water was boiled and then chilled to room temp.