Required Materials: Solids: KNO3 unknown concentration, KNO3 Liquids: Tap Water, DI Water Other: 1 burette, 1 1000 mL beaker, 5 test tubes, thermometer, heating pad Objectives: • To determine the effect of temperature of the solubility of a salt. • To construct a solubility curve for the salt. • To determine the mass of an unknown size sample of the salt. Theory: Solubility is a measure of t he amount of one substance that can be dissolved in a measured amount of another substance. In this experiment we are going to measure the solubility of KNO3 in water at various temperatures.
From this information, the percentage of salt verses water ions can be determined Ions are also produced in the liquid or solid state when salts interact with solvents (for example, water) to produce "solvated ions," which are more stable, for reasons involving a combination of energy and entropy changes as the ions move away from each other to interact with the liquid. These stabilized species are more commonly found in the environment at low temperatures. A common example is the ions present in seawater, which are derived from the dissolved salts. Procedure Obtain 250 mL beaker Weigh dry 250 mL beaker and record weight. Add 10mL of unknown salt and water solution.
6 grams of dried seaweed, cut into ½ inches should be places into a 150 mL beakers that will later be filled with ¾ distilled or deionized water. Then, the seaweed should be agitated with a stirring rod to remove monosodium glutamate. 2. After the water is poured off in the sink, 40 mL of distilled water should be added to the seaweed, and should be heated for 5 minutes with a Bunsen burner. 3.
Add 10 ml of ph 10 buffer to the same Erienmeyer flask. Start swirling immediately to dissolve, 7. Add 15 ml of water next. Use a squeeze bottle so you can wash the inside walls of the flask. 8.
The other lab partner should add the 20 mL water to the 100 mL beaker and stir for one minute. 19. Measure another 20 mL water using the graduated cylinder. 20. Add another 20 mL water to the 100 mL beaker and stir for one minute.
Measure the solution by right clicking on the beaker and choose pH meter *Then I had to measure the pH of 0.1 M sodium hydroxide Get a 100 mL beaker from the equipment menu Right click on the beaker, select chemicals, and add 50 mL of 0.1 M sodium hydroxide. Measure the solution by right clicking on the beaker and choose pH meter Part 2: *First add 35 ml of unknown acid a to 100 mL beaker. Select all chemicals from the toolbar in the chemicals section, choose unknown acid a. Put the volume at 35 mL in a new 100 mL beaker. *Then add two drops of phenolphthalein indicator to the beaker by right clicking, choosing indications, and adding 2 drops of phenolphthalein.
A hydrometer in an instrument that measures density by using a calibrated bobber. Salinity is measured in parts per thousand, expressed 0/00. Hypothesis: If the water being tested has more salinity, then the hydrometer reading will be larger, because when water has more salinity, it is denser. Materials/Drawing:  Beaker (150 or 250 ml)  Thermometer  Sea water  Beaker tongs  Tray – heat resistant  Balance & weights  Graduated cylinder  Hot plate  Stopwatch or timer  Safety glasses or goggles Procedure: 1. Use the balance to weigh the empty beaker, and record.
Independent Variables: • The range of pH, between 6-8 pH. Method: 1. Firstly, place the buffer tablets into a test-tube containing 20 ml of water (at room temperature). 2. Once the buffer tablet has dissolved into the water, add 10 ml of starch solution.
Discussion: The proteins solubility can be determine based on the salt concentration in the solution in a way that when the concentration is low, various charged groups on a protein molecule will be stabilized by the presence of salt. This actually attracts the protein into the solution and the solubility of protein is enhanced which is generally known as salting-in process. On the other hand, as the concentration of the salt increases, the point of maximum solubility of the protein is reached and cause the increase in salt concentration which suggest that there was less water available to solubilise the protein. As the water interaction become less marked, the protein-protein interactions became more important causing the protein to aggregate and come out of solution. This protein precipitation in the presence of excess salt is also known as salting-out process.
Gravimetric Determination of Sulfate Purpose The purpose of this lab is to determine the percentage of sulfate in the hydrate by precipitating the sulfate as barium sulfate. Materials Filler paper Sodium sulfate Graduated cylinder Bunsen burner Watch glass Beakers (250 mL, 400 mL) Rubber bulb Graduated pipette Beaker tongs Funnel Filter Paper Sodium Sulfate Drying oven Wash bottle Stirring rod Silver nitrate Hydrochloric acid Distilled water Small test tube Procedures First, .4861 grams of sodium sulfate was placed into a clean 400mL beaker. Exactly 200mL of water and 1mL of HCl was added to the same beaker. A watch glass was placed on the beaker and the solution was heated using the Bunsen burner to a gentle boil. The watch glass was removed with the beaker tongs.