* Repeat with the rest of the samples. PHASE CHANGE: * In the green ice bucket, scoop a beaker of ice. * Start stirring the beaker of ice * Start recording the temperature of the ice with a thermometer * Weigh the mass of the beaker and record the mass of the ice * Carry the beaker over to the calorimeter with a cup of ice and release it into the cup of 65mL of water already set up for you * Observe the temperature of the ice/water mixture * After the ice has melted all the way, heat up the water and observe the temperature and phase changes as it turns into steam * Record the temperature at which boiling begins * Look at your barometer and record this pressure Data Table: SPECIFIC HEAT OF METALS | Aluminum | Steel | Copper | Lead | Mass of metal (g) | 7.3547 | 20.0685 | 24.06 | 33.1229 | Volume of water (mL) | 100 | 100
Atomic Mass = 26.4/ specific heat. Equipment/Materials: samples of metals large test tube 400 mL beaker hot plate balance foam coffee cups thermometer Safety: • An apron and goggles must be worn in the laboratory. • Avoid contact with the hot plate. Procedure: 1. Place about 200 mL of tap water in a 400 mL beaker and place it on the hot plate.
For observing the reaction, use 8oz of water at four different starting temperatures: hot tap water, cold tap water, water heated in microwave, and ice water. a. For the hot and cold tap water, run the water until the temperature stabilizes. Fill the pyrex measuring cup to 8 oz. b.
With increasing temperatures the solute can be dissolved by a solvent during recrystallization. Experimental section Preparation of Chalcone To prepare chalcone 2.1mL of NaOH in was dissolved in 40mL of water and about 25mL of ethanol was added in a 125mL Erlenmeyer flask as soon as pellets were dissolved. Then 0.080 mole of acetophenone was stirred into the 125 mL flask, then place into an ice bath. At once 0.080 moles of bezaldehyde was added to the mixture and stirred all the while temperature was kept between 20-30°C. A stopper was placed on the flask while the mixture was stirring with stirrer for 11/2 hours.
Apparatus: • Safety glasses • Bunsen burner • Heat proof mat • Sodium thiosulphate • Hydrochloric acid • 100 ml of conical flask • Stop watch • 50 ml measuring cylinder • 10 ml measuring cylinder • Distilled water • Ice • Apron • Beaker Method 1. Collect safety equipment (apron and safety glasses) 2. Collect all materials and apparatuses 3. Set up the practical for room temperature test. 4.
Gather all materials 2. Heat 200mL of water in the beaker for 90 seconds 3. Place the bulb of one thermometer just below the surface of the water 4. Record the initial temperature at the top 5. At the same time, place the second thermometer bulb just at about the bottom of the beaker 6.
Next, cold water from the tap was collected in a plastic cup and measured in degrees Celsius. A handful of ice was then placed into the cup and sat for about 1 minute. The ice water was then stirred with the thermometer and the temperature was again collected in Celsius. Then the ice water sat for about 5 minutes and was stirred once again to collect the final temperature in Celsius. Once all of the temperatures were collected in degrees Celsius they were converted into degrees Fahrenheit and Kelvin.
Gently stir the pellets until the acid is dissolved by shaking the the apparatus. Lift the calorimeter lid and wash out its contents and the thermometer. Repeat this experiment using 50.0 mL of 1.0M acetic acid. Repeat experiment using 25.0 mL of each 2.0M sodium hydroxide and 2.0M acetic acid. Data Table(s): Reaction equation Mass of solid NaOH Initial Temp.
After which time, 2.1 mL of 30% hydrogen peroxide was added slowly followed by sodium hydroxide until a pH of 8 was observed. 20 mL of H20 and 10 mL diethyl ether were added to the flask. The contents were separated and the aqueous layer was rinsed with four 10mL portions of ether followed by 15 mL of sodium bicarbonate. The ether layer was dried with granular magnesium sulfate and then the solvent was removed by evaporation under reduced pressure. Lastly, the final product was analyzed by mass spectrometry and HNMR.
First I made a water bath by filling the 100 mL beaker with cool tap water. I then placed crushed ice in the 100 mL beaker so the water level was just below the top of the beaker. I sprinkled a little salt in the ice water and mixed it well. I then filled the test tube half full with distilled water and set the test tube in the 24 well plate. I inserted the digital thermometer into the test tube and took reading every 30 seconds until the readings remained constant.